Second Chance Peppers

EricaLeave a comment

Last month I blogged about giving up on plants. This month, I’m encouraging you to give some of them a second chance.

A caserole dish show a pile of large red peppers cut in half holding a mix of beef, corn, rice and other ingredients.
Dinner from my bountiful peppers! Photo: Erica Smith

Specifically, I’m talking about plants (vegetables or other) that you tried and failed with, and suspect that the failure may have been due to planting them in the wrong place, caring for them poorly, or maybe the happenstance of getting a bad seed or seedling. Sometimes our best-laid plans just don’t work out for, you know, reasons.

About five years ago I got some seed for Giant Aconcagua peppers and grew them in two subsequent years. Here’s what I said in this blog at the time, in an early October post:

I tried again with the Aconcagua sweet peppers, and had the same problems as before: a) the seedlings are slow-growing and weak; b) the peppers take forever to turn. I did get a couple of red ones, and the pale green ones are quite tasty and nice and big. I may try one more time, getting the seeds going at the end of January or the beginning of February, to see if I can produce seedlings rugged enough to go into the ground in May. 

I didn’t try again, though, because I thought these peppers were fussy and not worth the effort. This year, for whatever reason, I decided to give it another go. Wow, what a difference. I didn’t bother to start them super-early, and I’m glad I didn’t, because the seedlings started in mid-March grew as fast as all the other peppers, though they still began life with slightly paler leaves and a floppier structure. But they took off, getting to three feet high far earlier than they’d done before, and this time producing heavily with ripening in August rather than September or October.

A close up view of the pepper plants with a leaf and a number of red or turning red peppers hangin down through the interior of the plant.
Not the best photo, but you get the idea or how many peppers are on this plant. Photo: Erica Smith

And these are BIG peppers.

A large reddish orange pepper lays on a cutting board next to a ruler showing 9 inches long.
Photo: Erica Smith

They are not all 9 inches long, but most are close. They are more similar to a stretched-out bell pepper than a thin-walled Italian frying type, so great for all kinds of dishes.

I recommend these if you want a big pepper in your life. They absolutely must be supported, which you can do with the kind of medium-sized wire tomato cage that isn’t big enough for most tomatoes. And keep up with pruning or tying up branches! I lost a whole branch of green peppers in a thunderstorm because the weight got to be too much for the plant.

Why didn’t they work for me as well before? It could have been a set of weak seeds that didn’t have the best genetics for quick growth. Or I put the plants in spots that didn’t get enough sun or water, or had too much weed competition. Or a combination of those factors.

Seed catalogs use language that’s designed to make you jump at a particular plant variety, and we all know that, so given a poor performance, we say it was all hype, and we should never have believed the glowing description. But sometimes there’s truth behind the sales pitch, and we just need a second chance to find it.

Now, if I’d bought another seed packet and had the same poor results? Likely I’d have given up. Some plants just don’t work in a particular climate or setting, and enough trial and error lets us discover that. But one failure is not enough to declare the experiment over.

By Erica Smith, Montgomery County Master Gardener. Read more posts by Erica.

Invasive Ornamentals and Sterile Varieties

Maryland Grows3 Comments

When it comes to landscaping, a huge decision-making point is what we find visually pleasing… and often what pleases us visually ends up being something we are not very used to seeing, meaning that we pick plants that seem more exotic to us so we can marvel at their surprising (to us) beauty. This is all good and nice, but the problem appears when we realize that many of those plants appear exotic to us because they are exotic to the region we live in! This means that if we select them to plant in our landscapes, we are actually adding to our environment species that are not necessarily native to where we live… which can have pretty drastic consequences. In today’s post, I want to talk about a potential solution that has fairly recently been proposed to the use of such plants: sterile varieties.

What’s the deal with exotic plants?

Although not all exotic plants will have negative effects on our environment, some of them do. Those that do are considered invasive species, and they can create a lot of trouble in our local ecosystems. Invasive plants tend to grow faster than other native plants, often overrunning the spaces they grow in, spreading very quickly, and eventually “choking” or outcompeting local species, which end up dying out and/or becoming unable to survive in the presence of the invasive plant. Some good examples of this behavior of invasive plants in Maryland are the Chinese and Japanese Wisteria vines and the English Ivy, all of which effectively cover trees and can eventually choke and pull them down to their death.

View of a forest with vines covering the tree trunks up into the canopy.
In the Eastern USA, English Ivy does effectively take over forests. Photo: L. J. Mehrhoff.

In Maryland, this issue has been recognized not just by ecologists, but also by lawmakers, who have started to regulate the selling of specific species to properly support the protection (and recovery) of our local plant communities. Among the most recent additions to these regulations are the ban on selling several bamboo species, English Ivy, exotic Wisterias, and several very invasive grasses (among other species). You can check the most up-to-date list of these species at the Maryland Dept. of Ag. website: Maryland Prohibited Invasive Plant Law and Regulations. The Maryland Department of Natural Resources also hosts a website with a lot of information about exotic species (plants and others): Invasive and Exotic Species in Maryland

So what to do if we love the plants but do not want them to spread?

Ideally, if we do not want to harm local habitats, the best decision is to refrain from planting invasive species, because they are REALLY hard to properly control and prevent their spread (especially when there is bird-mediated fruit dispersal or stolon-mediated dispersal).

The forest in spring with many mature trees and Barberry invading the understory and dominating as the ground cover
Barrberry dominating the understory in a wooded setting. Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org
Bright red berries the shape of water drops hang along barberry branch.
Barberry shrubs produce many berries that birds and wildlife eat then distrubute. Photo: Chris Evans, University of Illinois, Bugwood.org

An alternative, however, is the selection of varieties that are unable to spread because they are sterile or do not have proper structures to do so. These are varieties that exist for some ornamentals/exotics, and that are in some cases exempted from the regulations that I was mentioning above. Some examples are non-invasive bamboo varieties, some Berberis cultivars (e.g., varieties “Lemon Glow”, “Crimson Cutie”), and even some almost-sterile Buddleja cultivars (e.g., “Flutterby”, “Lo and Behold” varieties developed by several University programs). A note on some of these cultivars is that although some of them are labeled “sterile”, they may or may not be fully sterile. Some of them have indeed been shown to, in some cases, produce some fertile offspring (although way fewer than their fertile counterparts!).

A green field with a forest line in the background. Purple wisteria vines are growing up many trees and shrubs, toppling one over.
Invasive Wisteria invades forests, vining themselves onto trees, pulling them down and eventually outcompeting and often killing them. Photo: M. Bakacs.

How to go about these decisions?

Generally, when considering exotic ornamentals for our green spaces, it is worth making it a practice of first informing ourselves about their potential for invasiveness. Then, if the potential is there, another good practice is to look for potential alternatives (e.g., do we really need to plant that specific plant?, are there less-harmful varieties?, are there native alternatives that can be planted instead?, can we properly contain the plant if it spreads?).

To make these decisions, a good tool to consider is the NC Extension Gardener toolkit, where species and varieties are listed and can be filtered out by (among other traits) their potential for invasiveness/weediness. The Maryland Invasive Species Council has also put together a list of species that have invasiveness potential (independently of regulations) and are thus of concern. A new tool from the University of Maryland Extension Maryland Native Plants Project can help you search and filter for native plants, so you can potentially choose a native plant which will suit your needs and benefit our eco-system: Maryland Native Plant Finder tool.

By Anahí Espíndola, Associate Professor, Department of Entomology, University of Maryland, College Park. See more posts by Anahí.

Anahí also writes an Extension Blog in Spanish! Check it out here, extensionesp.umd.edu, and please share and spread the word to your Spanish-speaking friends and colleagues in Maryland. ¡Bienvenidos a Extensión en Español!

Meet the Smoky-winged Beetle Bandit Wasp (Cerceris fumipennis)

Stacy Small-Lorenz1 Comment
Closeup of fingers holding a mostly black wasp with one yellow band on its abdomen and brown transparent wings splayed.
Smoky-winged Beetle Bandit Wasp Photo by: (c) hoops146, iNaturalist,(CC BY-NC) some rights reserved

I was transplanting a few Blue Mistflower (Conoclinium coelestinum) plants into my drainage swale pollinator garden last weekend when I noticed this new insect visitor to my blooming Rattlesnake Masters (Eringium yuccifolium; below). 

Spikey whiteish green flowers of Rattlesnake Master with a visiting Smoky-winged Beetle Bandit Wasp.
A Smoky-winged Beetle Bandit Wasp nectars on a Rattlesnake Master flower in the author’s pollinator garden. Photo: Stacy Small-Lorenz, UME 

This gentle beauty has a name that could have been penned by a cowboy poet – Smoky-winged Beetle Bandit Wasp (Cerceris fumipennis; Family Crabronidae) – and it plays an important ecological role. It parasitizes adult metallic wood-boring beetles of the family Buprestidae, including oak-boring beetles and the Emerald Ash Borer (Agrilus planipennis), an invasive beetle that is devastating North American ash trees, especially Green and White Ashes (Fraxinus pennsylvanica and americana). 

The Smoky-winged Beetle Bandit Wasp is native to Eastern North America and is the only North American wasp known to parasitize adults of Buprestid wood-boring tree pests, using the beetle bodies as hosts for their eggs and larvae. Scientists have even used this species for biosurveillance to monitor range expansion of the Emerald Ash Borer.

A combination of traits can help identify this native parasitoid wasp. Look for its black head, thorax, and abdomen and smoky-brown wings. Females may have a blue reflection to their wings. A distinctive cream or white apical band on the second abdominal segment is another key characteristic. Females have three cream-colored spots on the face, while males have two yellow triangles between their eyes. 

Smoky-winged Beetle Bandit Wasp adults are active mid-June into September in the northern part of their range. They are solitary ground-nesters that generally produce two generations annually. According to Heather Holm (2021), they usually burrow into compacted sandy or gravelly soil along rivers, in paths, gravel parking lots, or even baseball diamonds, frequently near forests where they can hunt for their beetle victims in the tree canopy, then bring them back to the nest. A female captures and injects a beetle with venom, then carries it in her mandibles to stash with several other paralyzed beetles in an underground nest chamber. 

The wasp carrying 2 shiny green matalic emerald ash borer beetle on a blue paper with a hole covering her nest opening. on sandy ground. There is a white golf tee holding the paper down.
A female Smoky-winged Beetle Bandit wasp brings a pair of mating Emerald Ash Borer Beetles back to her nest. The blue paper shown here will make it difficult for her to bring her victims into the nest, allowing biologists to collect the beetle bodies for pest monitoring. Photo: Philip Careless, Wikimedia Commons [CC BY-SA 3.0]

She’ll lay one egg on the top beetle that hatches after several days. She provides a larger supply of beetles for her female offspring than for the males. After hatching, her larvae will remain in their underground chambers over winter, feasting on beetles from their own personal stockpiles, before emerging as adults the following summer.

Biologists can observe the beetles that female wasps bring back to their ground burrows to document the presence of these tree pests.

These beneficial wasps are also “accidental” pollinators that pick up pollen on their bodies and transport it to other flowers while nectaring. They are harmless to humans and defenders of our forests, so two things we can do for them in return are protecting their nest burrows when we find them and providing some of their preferred nectar plants in a sunny spot near the forest, like rattlesnake master, swamp or butterfly milkweed (Asclepias incarnata or tuberosa), Virginia mountain mint (Pycanthemum viginianum), daisy fleabane (Erigeron strigosus) and Canada goldenrod (Solidago canadensis). These are relatively simple pest management practices for forest conservation that will also benefit many other pollinators.

While one species of wasp alone may not entirely solve the widespread dilemma of invasive wood-boring tree pests, there are other introduced and native parasitoid wasp species and woodpeckers that target earlier stages of the Emerald Ash Borer life cycle (egg and larval) (Shrewsbury 2026). Therefore, working in combination with other species, they could make a real difference for the next forest generation and therefore deserve our conservation attention.

By Stacy Small-Lorenz, UME Residential Landscape Ecology Specialist

This article was originally published in the UME IPM Weekly Report on August 7, 2026

References: 

Holm, H. 2021. Wasps: Their Biology, Diversity, and Role as Beneficial Insects and Pollinators of Native Plants. Pollination Press LLC. Minnesota, USA. 420 pp.

Shrewsbury, P. 2026. The Exciting Life of Parasitoids and Their Role as Biological Control Agents. Presented at the Stanton A. Gill Symposium: A Focus on Biological Control. August 5, 2026. University of Maryland Extension, Clarksville, MD.

Giving Up On Plants; or, When to Commit Plant Murder

Erica2 Comments

I think we’ve all been there. Everything else in the vegetable garden is going well, growing as it should, producing bountifully, getting the better of challenges. And then there’s the one plant that just… isn’t. (Or more than one that just aren’t.) Maybe, though, given a little more time, a little more fertilizer, a little more effort, a little more love… it might pull through? Or is it taking up space for no reason? Worse, is keeping it around bad for your more successful plants?

When, in fact, is it the right time to commit plant murder?

I can’t help joking, but of course we all hate killing plants that we’ve tried hard to nurture, maybe even growing them from a tiny seed. But let’s face it, there’s only so much space in a garden, and the season will be over soon. We don’t want to waste the time and square feet that we have. Most of the plants in an edible garden are annuals, and with these we need to make decisions soon. With perennials, maybe you can wait until next year to see if conditions improve.

How do you figure out when and if you should pull a plant out of the garden? Well, it’s like a detective story in reverse; first, you need to be an investigator, and then a potential killer. Find out what’s wrong with the plant; assess how bad the problem is and what the consequences might be; and then make a decision based on the facts.

The HGIC website is a good place to start. If the plant in question is a vegetable, I suggest starting with the Vegetables Grown in Maryland page, select your vegetable, and visit the “Growing ___ in a Home Garden” article. From there, you can explore the list of potential problems. If you can’t figure it out from there, or from more searching online, you can contact the Ask Extension team, or ask your county’s Master Gardeners.

The problems you might encounter with plants include:

PESTS

Pest problems are often fixable. Follow the advice given at HGIC or on other regional Extension websites, and you are likely to be able to control the pests sufficiently to get a crop. However, there are a few instances where giving up on the plant is a better option.

  • The pest has killed the plant or come close to killing it. For example, squash vine borer can take out a squash plant in days, and if you don’t remove the pest in time, or it has destroyed most of the main stem, you will not be able to revive the plant. Flea beetles can eat most of the foliage of young eggplants, to the point where they can’t survive. But don’t jump to the conclusion that a few holes mean a devastating invasion.
  • The pests keep coming back even when you remove them. This happens often in community garden situations or when you have close neighbors growing the same plants. Maybe you can work together to get rid of the pests, but if that’s not an option, you might consider switching to a less susceptible crop.
  • There is a solution, but you can’t implement it right now. This is particularly true of animal pests—maybe you need to fix a fence or fill a hole, and it’s best done in the off-season. Or you have overplanted a bed, making it difficult to reach plants to remove pests. The easiest fix may be to remove the temptation and limit the pest’s options in the process.
A leaf of a squash plant with holes and yellowing from squash bug feeding.
Squash bug damage in plants I couldn’t get to because I overplanted my small garden. Photo by Erica Smith

Remember that not dealing with insect pests as soon as possible means that they are able to complete their life cycle and make more pests! If you do remove a plant that is infested, try putting it in a black plastic trash bag and leaving it out in the sun until the pests are dead. That way, you haven’t just chased them off to attack another plant. You can then put the bag in the trash or even add the contents to your compost if the plant isn’t also diseased. Speaking of which…

DISEASES

If you suspect a plant disease, diagnose it and read up on its prognosis. Does it kill a plant fast, or is it slow-working? How lethal is it and how fast does it spread? Again, it’s likely you can keep plants going for a while, for example with a common fungal disease like early blight on tomatoes, but there are cases where plant removal is advisable. If you do pull plants, put them in the trash rather than adding the debris to your compost.

  • Diseases that spread quickly. If you see the disease spreading to other plants, and it can’t be stopped by removing affected foliage and other plant parts, you may need to pull the plants that are diseased. This is especially true in truly destructive diseases like late blight (luckily, this is uncommon in Maryland!), but also with more common issues like bacterial leaf spot, which has devastated some of my recent pepper crops. Remember, most diseases are specific to particular species or families, so you don’t need to pull out your whole garden because one type of plant is affected.
  • Diseases that will prevent a plant from producing. Examples include bacterial wilt that kills a cucumber overnight (easy call), or mosaic virus that lets a squash plant continue to grow but will kill it before it has any viable fruit (harder to make the decision to pull). In perennial plants such as fruit trees, you may lose a crop one year but not the next; on the other hand, if the disease comes back for several years running despite treatment, why are you still trying? (It took me a couple years of fire blight on quince to decide I wasn’t meant to grow it.)
  • Multiple factors, including disease. A disease alone might not be enough to make you decide to pull a plant, but if it’s also battling pests or drought, or producing very little for some other reason, it might not be worth keeping.
A red bell pepper with rotten spots on the skin.
This pepper damage was likely caused by bacterial leaf spot. Not worth keeping the plants going if the result looks like this! Photo by Erica Smith

OTHER

  • Failure to thrive. This is a generic term for “just not cutting it”: looking puny and sad. Maybe the seed you grew this plant from was the worst one in the packet; maybe it got stressed from being in a pot too long; maybe the soil conditions in that particular spot are poor; maybe we’ve had crazy weather and the plant just can’t cope. Some TLC and fertilizer may help, but not always.
  • Bolting. Cool-weather crops often last into the summer, but there’s always a point when they want to go to flower, and no amount of pruning will stop it.
  • Failure to produce correctly. Maybe the plant looks healthy but it isn’t making what it’s supposed to make. Root vegetables that don’t make roots; beans that don’t bean; broccoli that won’t head up. A little extra time and some fertilizer may help, but possibly not. Pull the plant; do a soil test and plan an appropriate fertilizer regimen next year; look at conditions generally (enough sun? enough water?).
  • Need the space for something else. In a small garden, we sometimes have to make choices about what hangs in there and what gets ousted. If you want to grow kale and there is nowhere else to put it but where the tomato plant is covered with early blight and producing many fewer fruits, it may be time for the tomato plant to go.
A weak looking pepper plant with only 1 small fruit starting to grow.
This fish pepper has been looking sad all season. Might be a soil issue, or stress due to root crowding in the pot. Or something else. I still don’t want to pull it out, so I gave it some fertilizer and a pep talk. Photo by Erica Smith

In general, remember that failures are a learning experience! Sometimes we learn about a fundamental flaw in our garden or in our practice; sometimes we learn that a particular plant isn’t for us (but give it another try first!); sometimes we can just chalk up failure to a bad year or one fixable mistake. Pulling a plant is also an opportunity to put another plant in its place. (Probably not one of the same species, because the problem may affect it too.) Succession planting is made easier by thoughtful but relatively quick decision-making; get out that sick squash and you may still have time to put some bush beans in, or to get the space ready for fall planting.

And as gardeners, we always continue to hope things will be better next time!

By Erica Smith, Montgomery County Master Gardener. Read more posts by Erica.

Why don’t I see pollinators on my plants?

Maryland GrowsLeave a comment

One of the most widespread actions implemented to support pollinators and other beneficial organisms is the planting of (native) flowering plants. The idea is that if we offer food to pollinators, they will come. However, we may have planted the plants, but the pollinators still aren’t coming. What could be happening? In this post, I will cover some biological reasons why this may be happening, and some solutions to consider.

Not all flowers are made equal

To a pollinator’s eye, not all flowers are the same. As we mentioned in other posts, each pollinator group (e.g., butterflies, birds, bees, flies…) has a different shape and different sensorial and physical abilities. While a butterfly may be able to reach the nectar at the bottom of a very tubular and long flower, a fly may not. Likewise, a large pollinator that is physically stronger than a small pollinator may be able to enter a very closed flower. Further, a night pollinator can obtain nectar from plants that offer it at night, while it will not get anything from those that offer it during the day…. I guess you see my point. Essentially, pollinators prefer flowers that make it easiest to locate and harvest resources like nectar and pollen. These differences mean that unless those flowers are present in a landscape, certain groups of pollinators may not be seen at all.

A grid of 9 flowers in various shapes and colors and different pollinators from bees and wasps, to moths and birds.
Different floral shapes and colors make floral rewards more easily accessible to different pollinators. Photos: J. of Pollination Ecology.

Not all flowers necessarily offer what a pollinator is after

Pollinators visit flowers to obtain something they need. That something may be food (e.g., nectar, pollen, parts of the flower), materials for reproduction (e.g., perfumes), materials for nest building (e.g., resins, floral oils), or simply a place to overnight, stay warm, and/or mate. As a matter of fact, not every single flower serves all those needs, making the pollinators end up “sorting themselves” among the plants that offer what they need.

A yellow blooming flower cluster with a bee climbing inside one of the blooms.
A bee of the genus Chalepogenus visiting a flower of Calceolaria dentata (native to Chile and Argentina) to collect floral oils and pollen. Photo: A. Espíndola.

Let me give you an example. In my research life, I work on a specialized pollination system that involves flowers that do not offer nectar at all, but instead offer floral oils (and pollen) in exchange for pollination (you can read more about this from the blog post: Why Do Pollinators Visit Flowers?, May ’20). These flowers are called lady slippers and belong to the Pan-American genus Calceolaria. When we observe which pollinators visit the flowers, we see that it is mostly bees who specialize in collecting floral oils (in our case, bees of the genera Centris and Chalepogenus), and basically nothing else. In landscaping, filling our yards with only one specialized flower type drastically limits pollinator diversity. For instance, if we only planted oil-producing flowers, we would not see many diverse pollinators. This highlights a key rule: the rewards a plant offers dictate the visitors it attracts. Just as varied flower shapes are crucial, providing a diverse mix of nutritional rewards—like nectar, pollen, and oils—is the best way to boost the number and variety of pollinators in our green spaces. As for the floral shape I was referring to, planting species that offer different types of rewards is a very good way to increase the number and types of pollinators we see in our green spaces.

The flowers do not necessarily want to share too much

Plants attract pollinators because they can get pollination from them, which allows the plant to reproduce. From a biological point of view, a pollinator will be a good one if it carries pollen from the stamens of a flower and makes it land on the stigma, so it can germinate and then fertilize the ovules. This is all good and nice; the problem, however, is that many pollinators use pollen as food. This creates a conflict between the plant’s and the pollinator’s interests: a plant needs the pollen (that contains its sperm) to not be eaten but to fertilize its ovules, but many pollinators just want to eat the pollen (and they have good reason for this, since a pollen grain is extremely rich in nutrients!).

A black and white microscope image of pollen grains. Some are spikey, some round, and some beanshaped with cantelope rind-looking texture.
Pollen grains have different structures and shapes. Photo: Dartmouth College Electron Microscope Facility.


As a response to this conflict, some strategies have evolved that somewhat “control” the feeding on pollen that pollinators may do. In fact, plants protect their pollen with physical structures that make it hard to be broken by pollinators. Some of these pollen grains feature spikes and thickened walls, which force pollinators to use specialized tools to break through them. Along with this physical “shield”, pollen grains often contain what are called secondary metabolites. These are chemical compounds that make the pollen indigestible or toxic, unless the organism trying to eat it has evolved ways to tolerate those compounds themselves. Closely related plants produce similar chemical compounds; the unique chemistry of a plant family dictates which pollinators can digest its pollen. This leads to different levels of floral specialization on the side of the pollinators. Pollinators will only try to visit plants that offer pollen they can digest, which again, restricts the flowers they visit. As for the previous points, increasing the different types of plants by having representatives of different plant families can increase the variety in the chemical quality of the pollen offered, attracting and supporting different types of more or less specialized pollinators.

By Anahí Espíndola, Assistant Professor, Department of Entomology, University of Maryland, College Park. See more posts by Anahí.

The Need to Weed

Erica2 Comments

I recently got back from a 10-day trip away from home, and had to brace myself before I approached my community garden plot. I hoped there wouldn’t be pests or diseases to deal with. I was pretty sure the tomatoes would have escaped the bounds of their cages. But the one thing I knew I’d encounter was WEEDS.

A close up of various weeds in a garden setting where you can see some leaves of corn poking through.
Weeds including wood sorrel and unwanted grasses in a bed growing corn and onions.
Large okra leaves in a raised bed with various weeds underneath them.
SO MANY WEEDS in the okra bed at the Derwood Demo Garden

It was not as bad as I’d feared, but I still had to deal with a lot of unwanted plants, which is basically what weeds are. All plants have their place, but that often isn’t in our vegetable gardens, flower beds, or landscapes. I often hear from people that we should let certain weeds grow, because they are part of the ecosystem, because they support pollinators, or because they have other uses, such as being edible. In some very specific cases, these are good arguments. If I have a native plant come up in the middle of a veggie bed, I might let it grow, or more likely I would transplant it to another location in my yard (or into the row of native flowering plants I’ve established in my community garden plot). If it’s a non-native invasive that is about to produce around a thousand seeds that will spread the plant all over my yard or the community garden, I’m going to yank it, even if it has pretty flowers that the bees like. I might also let an edible weed like purslane grow, if I’m in the mood to harvest it and use it, but I’d try to contain it before it spreads too far.

Here are the main reasons that you should remove weeds from your vegetable garden, even if it’s a lot of work and you don’t feel like it:

  • Competition. In some environments, growing lots of plants close together is beneficial. Even vegetable gardens can benefit from close planting in some circumstances, to shade the soil or to confuse herbaceous insects. But weeds are weeds because they are survivors, and they tend toward domination. They will swallow up your desirable plants in no time, suck up all the water and nutrients, and provide you with nothing.
  • Reproduction. Weeds spread like crazy either via seed or by suckering roots. If you have one weed this year, next year you will have hundreds. This is bad enough in your own backyard, but if you have close neighbors, or if you’re in a community garden, you are not going to be popular. (In a community garden, you may be ousted before next year, depending on the rules and how they’re enforced.)
  • Pests and diseases. Each weed is part of a particular plant family, often the same family as some vegetable you’re trying to grow. It may harbor some of the same pests and diseases as that vegetable. Guess which plant is going to shake off the problems faster, and which one will tenderly succumb?
  • Ticks. Love to hide in weed patches and hitch a ride as you pass through on your way to the squash. There might also be other critters lurking in out-of-control weed jungles, such as snakes (good to have around, but startling), or entire rabbit families in a nest. Just to name a few. Plant a native hedgerow and let them live there, not in your tomato bed.
  • Aesthetics. I put this last for a reason, but even if you personally don’t long for a tidy garden, keep in mind that vegetable gardening as a pursuit sometimes gets bad-mouthed for being “messy” and any actually messy gardens can contribute to a stereotype. HOAs that forbid front yard veggies, neighbors that complain about completely hypothetical rats, they all learned their prejudices somewhere. Don’t let it be your garden. We all want more homegrown produce in the world, not less.

So get out there and pull the weeds! And then, think about how to stop them from growing in the first place. Here are some things you can do this summer and beyond:

  • Mulch. Put something over your soil, preferably an organic mulch like shredded leaves, straw, or dried grass clippings. You can even use weeds as mulch if they don’t have seeds on them. Compost can be a mulch if you are sure it’s been heated enough to kill weed seeds. Synthetic mulches like black plastic or weed barrier fabric are also an alternative, though they won’t add organic matter to your soil. When you disturb the soil to put in plants or seeds, try to cover it again to prevent the germination of weed seeds that have been brought to the surface. (Obviously, don’t put a thick layer of mulch over the seeds you just planted.) Mulch is also great at keeping the soil from losing moisture in the heat, and maintaining it at an even temperature. And it may help prevent fungal spores from splashing up from the soil onto your plants.
  • Learn to ID weeds. Know your enemy! As you pull a weed, use a plant ID app or other source to identify it. After some time and work, you’ll know the common ones and you can learn about how and when they reproduce. Do I have to get the whole root out (yes, for perennials) or can I just remove the top of the plant before it goes to seed (usually, for annuals)? How early in the year do I have to get out there to start pulling weeds? (Earlier than you think, alas.) The other advantage to knowing weeds is that you’re less likely to mistake them for the plants you want to grow, and vice versa. Close observation works equally well for identifying veggie seedlings. Be an informed gardener!
  • Think about growing in containers. Refreshing the potting mix every year will definitely mean fewer weeds.
  • Speaking of which… think about containing or restricting plants that are desirable but act like weeds. Various mints and their relatives, shiso/perilla, leaf fennel, some amaranths… I have personal knowledge of how badly these spread, and I’m sure every gardener has a similar list. Whether you trap the roots in a pot (on a paved surface, in the case of mints) or make very sure to cut off the tops before the seeds go flying, it’s a responsible thing to do and will spare you a big surprise come the next growing season.

And lastly, be patient. Weed seeds lurk in the soil for many years, so they probably will keep coming back. There will be setbacks. But eventually, things will get easier and more enjoyable, and (mostly) weed-free.

By Erica Smith, Montgomery County Master Gardener. Read more posts by Erica.

Small but mighty. The amazing ground-nesting bee!

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The summer is almost here, and if you are like me, you have already been outside and seen a bunch of tiny bees digging, digging, digging, and buzzing around flowers. Who are these little ladies? And what on earth (pun intended) are they doing? In today’s blog, I want to explain a bit about these super powerhouses, how they do what they do, and point to some of these cool bees that we can find right here in Maryland and our general region.

What are ground-nesting bees?

As its name indicates, ground-nesting bees are bees that nest in the ground, mostly by digging their nests. Ground-nesting bees are found in several families of bees, and being a soil nester/digger is actually one of the most common nesting strategies among solitary bees. In these bees, once the female finds a good nesting site, she starts excavating it to create an underground nest, which often has several brood cells, in which the larvae develop. These nests are usually found in spaces where the vegetation is sparse or the soil bare, and can sometimes be built along with other nests of the same species, leading to communal nesting areas. It is because of this preference for relatively open ground that it is often recommended that at least some uncovered ground is left in our green spaces, which helps provide habitat for their establishment.

A tiny bee is seen crawling out of a mound of soil on the ground.
Ground-nesting bee coming out of her nest. Photo: Colleen (CC0).

How do ground nesters build their nests?

As good miners or soil diggers, ground-nesting bees also have specific behavioral and morphological traits that make them good at what they do. Bees that excavate have modified leg structures that allow them to easily move within tunnels, strong mandibles that they use to actually dig the cavity, and modified extremities of the abdomen (the pygidial plate) that function as sorts of trowels and allow them to pack soil on the walls of the cavity they are digging.

Along with having the right tools of the trade, these bees are also selective of the type of soil they use to build their nests. Most ground-nesting bees prefer soils that are not too compacted, with at least some sand content, which makes them easier to dig through. This means that it is more likely that we will find these bees in rockier/sandier soils than in super clay-y ones. As a matter of fact, many ground-nesting bees are associated with dune nesting, and because dunes are often endangered habitats (because they are often disturbed/destroyed by human activities), many sand-nesting specialists end up becoming endangered as well. And as a fun fact about soil choice, bee experts think that because finding “good soil” is so important for the survival of these bees, bees tend to become associated with specific spots for nesting, with the nesting site becoming a sort of “family place”, where several generations of females from the same family line come back to nest over the years/generations.

A close up of the pygidial plant which is a small darker triangular structure at the tip of the bee's abdomen.
The pygidial plate is a structure present at the tip of the abdomen of ground-nesting bees that functions as a trowel. Photo: MN Native Bees.

Because digging through the soil with their mandibles (and sometimes their legs) is hard work, bees usually tend to choose the best timing to start their digging. In fact, the hardest part of the soil to dig through for a bee is the surface, which is often the most compacted. For this reason, bees tend to start digging after the soil has become moist (e.g., after rains). Incredibly, some ground-digging bees are even able to add, if needed, secretions or even nectar to humidify and loosen the soil! Once the bee has started her excavation, she continues digging deeper and bringing soil out of the construction area, which leads to all sorts of “mounts” being built around the nest entrance and sometimes chimney-looking structures.

What are some ground nesters from Maryland?

Andrena vicina – The neighborly mining bee

a close up of a bee gathering pollen from white flowers
Andrena vicina. Photo: K. P. McFarland (CC0).

This Andreniid is relatively large (about 1- 1.5 cm), present in North America and common in the Eastern USA. This species received that cute name because it is one of those that builds communal nesting areas (“neighborhoods”). In Maryland, the species is active right now (~June/July) and is generally seen visiting many native plants and crops. In particular, this is one of the known visitors of, among other plants, Rhododendron and Azaleas, several heather family plants (like Vaccinium, Kalmia), as well as several rose family plants (Prunus, Rubus).

Augochlorella aurata – Golden sweat bee

a tiny metallic green sweat beed in the center of a yellow flower

Augochlorella aurata. Photo: C. Martin (CC0).

This is a species in the Halictid family, and is called a sweat bee because it is often found collecting sweat (for water and salts). This is one of those tiny bees that you may find landing on you on a hot day, really committed to not letting go of your skin! This particular bee is relatively easy to recognize because it is small, metallic-looking, with beautiful green/golden iridescence. This bee is not fully solitary and is a species recognized to display primitive eusociality (for example, honey bees are true eusocials). In this species, there is a queen that starts a nest, and across the season, generations of first infertile and later fertile workers are produced. By the end of the season, the fertile workers are inseminated and disperse to overwinter. This bee species is pretty generalist in its choice of plants, known as a pollinator of many crops (e.g., apples, tomatoes, watermelon) as well as native plants.

By Anahí Espíndola, Associate Professor, Department of Entomology, University of Maryland, College Park. See more posts by Anahí.

Anahí also writes an Extension Blog in Spanish! Check it out here, extensionesp.umd.edu, and please share and spread the word to your Spanish-speaking friends and colleagues in Maryland. ¡Bienvenidos a Extensión en Español!