Maryland Grows

How to Identify Insect Pests in Your Vegetable Garden – Featured Video

Mike Raupp, “The Bug Guy” for the University of Maryland Extension, explains how, like a crime scene investigator, you can use clues to find out what types of insects are causing damage in your garden. Look for telltale signs like chewed leaves, discoloration, distortion, dieback, and insect products.

Great Grasses for Maryland Landscapes

What are some beautiful plants that are relatively easy to maintain and unappealing to deer? Take a look at the ornamental and native grasses!

Little bluestem grass

Little bluestem (Schizachyrium scoparium) ‘Standing Ovation.’ Photo: Mikaela Boley

Ornamental grasses are plants that provide year-round beauty, texture, persistent ground cover, erosion control, and a variety of additional benefits. They are:

  • Available in many heights and forms suitable for different landscape situations
  • Helpful in trouble spots like slopes or places where a living screen is desired
  • Relatively easy to maintain by pruning back once each year
  • Generally distasteful to deer.

If you are planning to add native plants to your landscape, add a few grasses to the mix. Grasses provide winter shelter for beneficial insects and seeds for birds. Some even have interesting associations with small butterflies called skippers. For example, the Leonard’s Skipper uses little bluestem, switchgrass, poverty oatgrass, and bentgrass as host plants. That means that when these insects are in their juvenile stage (caterpillars), they can only feed on these types of grasses to survive. As adult skippers, they fly off to feed on the nectar of other flowering plants. They are delightful to watch “skipping” around a butterfly garden!

ornamental grasses in winter

Ornamental grasses provide textural interest in a garden in the winter. Here they are beautiful in combination with remnant seedpods and the red berries of winterberry holly in the background. Photo: C. Carignan

There are about 350 species of grasses in Maryland. They are the primary plants found in native meadows and there are even grasses, such as Eastern bottlebrush grass (Elymus hystrix), that thrive in our state’s shaded woodland areas.

Eastern bottlebrush grass

Eastern bottlebrush grass (Elymus hystrix) Photo: Chris Evans, University of Illinois, Bugwood.org

The Maryland Native Plant Society has named 2020 “The Year of the Grasses”. All year long, through their monthly events and plant walks, you can learn about Maryland’s grasses and their native habitats.

Ornamental and native grasses are readily available at garden centers and native plant sales. Be sure to avoid invasive ones like Chinese silvergrass (Miscanthus sinensis).

switchgrass

Switchgrass (Panicum virgatum) ‘Shenandoah’. Photo: Mikaela Boley

For some great choices, check out my colleague Mikaela Boley’s excellent guide to Ornamental and Native Grasses for the Landscape on the Home & Garden Information Center website.

If you already have ornamental grasses in your landscape, now is a good time to prune them. Grasses that turn brown in the winter should be cut down to about 2″ above the ground in early spring before new growth begins.

By Christa K. Carignan, Coordinator, Digital Horticulture Education, University of Maryland Extension Home & Garden Information Center. Read additional posts by Christa.

On the Go: Orchids at Longwood Gardens – The Garden Hoes Podcast

Garden Hoes Podcast

We have a special bonus episode for you this month. The Gardens Hoes went “On the Road” to Longwood Gardens in Kennett Square, Pennsylvania, to learn more about their yearly orchid exhibit. We sat down with Greg Griffis, senior horticulturist and orchid grower, to ask him about the exhibit, orchids, and tips for growing them. The Orchid Extravaganza is an annual event at Longwood Garden that runs through March 22. Longwood Gardens consists of 1,077 acres, with gardens ranging from formal to naturalistic in design. Formidably, the Conservatory encompasses 4.5 acres of greenhouses. This lush winter oasis is transformed from January to March, with over 6,000 orchids. As you wander through the conservatory you’ll see Phalaenopsis orbs hanging above the Patio of Oranges, to Lady Slipper orchids tucked in along the Fern Passage, to delicate Cattleya in the Orchid house, orchids magically transform every space. 

Great news! We are now available on both iTunes and stitcher, making it easy for you to listen to The Garden Hoes on the go! To listen to our latest episode click here.

You can find out more information about this event, Longwood Gardens, and their other events by visiting longwoodgardens.org. If you can’t make it to Longwood Gardens for the exhibit check out “Everything About Orchids.” This free online course hosted by Longwood Gardens offers valuable insights from experts at Longwood Gardens through video lectures and discussion forums. 

Fountain Phalaenopsis

Fountain Phalaenopsis: upon entering the Conservatory you’re greeted by a sea of yellow Dancing Lady orchids (Oncidium) as light pink Phalaenopsis spill over above them. (Photo taken by: Rachel Rhodes)

 

Pierre the cat

Pierre: Longwood Gardens is home to a diverse feline family. They supply ample entertainment and companionship for all who grace the gardens. On this trip, we were lucky to have Pierre guide us through the Conservatory. His favorite spot was the large Orchid Panels featuring Phalaenopsis in the East Conservatory. (Photo taken by: Rachel Rhodes)

 

Phalaenopsis_Rose

Phalaenopsis_Rose: dark pink Phalaenopsis gently lead you through the Rose House. (Photo taken by: Rachel Rhodes)

 

Phalaenopsis

Phalaenopsis: Phalaenopis Tai Lin Red Angel ‘V31’ Orchids gracefully hang from elevated columns on the west side of the Exhibition Hall. They are rarely displayed outside of Asia. (Photo taken by: Rachel Rhodes)

 

Paphiopedilum Invincible ‘Spread Eagle’

Paphiopedilum Invincible ‘Spread Eagle’: is a beautiful slipper orchid hybrid that originated by Wrigley in 1911. It is a cross of Paph. Hirsutissimum x Pap. Monsiuer de Curte (Photo taken by: Rachel Rhodes)

 

Greg Griffis

Greg Griffis, senior horticulturist, and orchid grower, sat down with the Garden Hoes to talk about all things orchids. (Photo taken by: Emily Zobel)

If you have any garden questions or topics you like us to talk about, you can email us at Gardenhoespodcast@gmail.com Garden Hoes is brought to you by UME. Mikaela Boley- Senior Agent Assoc. (Talbot Co.) for Horticulture, Rachel Rhodes- Agent Assoc. for Horticulture (QA Co), and Emily Zobel- Agriculture Agent (Dorchester Co.).

Pawpaws: The Tropical Fruit From Our Forests

Spring is almost here and now we can start thinking about trees to plant if we did not get to that in the fall. Thinking about trees for my garden, I came back to one I have been considering for a while now — one that gives delicious fruit, is native, makes me think of tropical lands, and is not liked by deer! Today’s post is going to be about a little-known tree that’s native to our region, and whose fruits were apparently one of George Washington’s favorites: pawpaws!

What are pawpaws?

Pawpaws are trees that belong to the same plant family as chirimoyas and custard-apples (Annonaceae, the soursoup family; Figure 1). From a botanical perspective, pawpaws are really special because they are the only member of their family adapted to growing outside of the tropics and able to survive our temperate climate.

pawpaw and related fruits

Figure 1 – Pawpaws (left), chirimoyas (top right) and custard apples (bottom right) are all in the same plant family, but pawpaws are the only group adapted to growing in temperate climates.

All pawpaws grow in southeastern North America, but the most common and widespread species is the common pawpaw, Asimina triloba, which is very abundant in our region. The common pawpaw is adapted to growing in well-drained and fertile habitats, such as those found in our forests. I promise you that if you ever walked in a forest in the area, you have seen hundreds of pawpaws growing in groves (Figure 2).

Pawpaw grove

Figure 2 – Pawpaws grow in well-drained fertile soils, and are common in our forests where they often grow in groves. Photo: Katja Schulz.

Why are pawpaws such a “thing”?

Besides being great native trees that grow well in our region, pawpaws have the most delicious fruits. They are considered the largest edible fruits indigenous to the continental United States. The fruits look a bit like a green mango from the outside, but are white/yellow and fleshy in the inside (Figure 3).

pawpaw fruit

Figure 3 – Pawpaw fruits are green on the outside and white and fleshy on the inside. Note the very large seeds. Photo: Elizabeth.

Their flavor is such a delicious one that I always relate it to tropical fruits. People more technical than I am in terms of flavor description say that it is a custard flavor, close to that of bananas, pineapples, and mangos. In any case, believe me when I tell you that these fruits are absolutely delightful and can be eaten fresh, in yoghurts, in cakes, as jams, or frozen in ice-cream!

Why didn’t I know about this before?

That was my very question the first time I tried them! It turns out that producing pawpaws for selling is not super simple. In fact, the fruits are fragile and thus can’t be transported long distances, which reduces their marketability. This means that pawpaws are usually produced and consumed locally. If you do not happen to know somebody with some trees on their land, you probably never got to try them.

Also, the pawpaw fruit season is relatively short (end of the summer), which means that one has to be in the right place at the right time to eat them. In season, pawpaws can be purchased at local farmers’ markets or on farms. You can also try to find them in the forests of the area, where you will be able to smell the sweet aroma of the fruits while you hike or bike. However, be sure to check property rules; harvesting plant materials from park lands is typically prohibited.

Why are you talking about this now? It’s not pawpaw season yet!

That is correct. However, it is pawpaw planting season now, and soon will be pawpaw pollination season, both needed to actually get the delicious fruits in the summer. So, how to plant and pollinate them?

Pawpaws can be grown from seed, but the simplest way to get one for your land is from a nursery. Several nurseries in the area sell pawpaw trees, and your best choices are those which grow trees that are adapted to your local conditions.

Pawpaws are not hard to grow and can be actually cultivated in your own back or front yard! Further, some counties and cities provide financial support to plant these native trees (see for example, Chesapeake Bay Trust and the Maryland Department of Natural Resources).

Pawpaw trees start producing fruit a couple years after planting. However, fruit production is a bit different from that of other fruits you may be growing. In fact, fruits will form only if there is cross-pollination (see this other post), since a pawpaw is not able to properly self-pollinate. This means that pawpaws need pollinators to produce fruit.

pawpaw flower

Figure 4 – Pawpaw flowers have evolved to attract and trick flies and beetles by looking dark and smelling like ripe fruits, the insects’ preferred food and egg-laying site. With this trick, the plant cross-pollinates their flowers without offering any reward to the pollinators. Photo: Judy Gallagher

Pawpaws are pollinated by flies and sometimes beetles, which the flowers attract with their maroon flowers and their ‘yeasty’ aromas (Figure 4). These scents are known to ‘trick’ the pollinators into visiting the flowers, mimicking the odor of ripe fruits that these insects prefer to feed on or lay their eggs. Flowers then attract these pollen dispersers, who, while visiting the flowers, will cross-pollinate them without their will.

You can imagine by now that having more than one pawpaw on your land or in the surroundings of your house will increase fruit production. It will then be more likely that the fooled pollinators will have visited another plant and thus carry pollen when they visit your tree.

Alternatively, if you would like to be absolutely sure to get a good pawpaw crop, you can cross-pollinate them by hand. To do that, get a small brush, pick pollen from the anthers of one flower (check the drawing here to find them), and transfer it to the stigma of another. That way you will get to live your best pollinator life! 😊

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

Build an herb spiral

Many gardeners are looking for ways to use space efficiently and get the most out of a given area, and at the same time create the best environment for their plants. Every garden should have herbs, but sometimes they can be tricky to grow. They want different kinds of soil, so putting them all in one bed doesn’t always work. Some are perennial and some annual or biennial. Some demand full sun and some can benefit from a bit of afternoon shade. Most want great drainage. And of course they take up space. What’s one solution? An herb spiral.

IMG_6407

My herb spiral last fall, with pineapple sage, rosemary, lavender, and the trailing plant called Cuban oregano

 

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March Tips & Tasks

Grass seedlings

  • Late winter-early spring is considered the second-best time to seed your lawn make repairs, or cover bare areas. The best time is late August through mid-October. Seeding should be completed by late April.
  • Begin to fertilize houseplants again. The increase in natural light will prompt them to grow.
  • This is a good time to repot and divide houseplants. Use lightweight, well-drained soilless potting mixes that contain ingredients such as peat moss, vermiculite, and perlite.
  • Now is a good time to prune roses. Roses typically experience some winter kill. To determine whether or not a branch is alive, simply scrape the bark with a sharp knife and look for green tissue. If it is brown, prune off the cane.

Let Spiders Help in Your Vegetable Garden

A few years ago during the early spring, my brother, mother, and I noticed several quarter-sized, brownish-colored egg cases in our high tunnel. Our research taught us they were gifts from black and yellow garden spiders, Argiope aurantia. These spiders are also called yellow garden orb-weavers, writing spiders, or zipper spiders. This made sense, as the tomato vines are trellised to 8 feet high and provide the perfect environment for these magnificent arachnids to spin large circular webs, high off the ground, which contain a highly visible, zig-zag pattern in the center that is called a stabilimentum.  

garden spider egg cases

Four black and yellow garden spider egg masses in the back of the high tunnel frame were laid in the fall of 2019. The spider webbing provides protection from predators. Each egg case contains hundreds of baby spiders. Photo: Ashley Bodkins

We assumed that the eggs had hatched the previous fall and opted to not bother them and go about cleaning up and preparing for the new growing season. Little did we know, each egg case contained hundreds of baby spiders just waiting to make their escape, which happened later that spring and left our high tunnel completely overrun with spiders! 

Fortunately, these black and yellow garden spiders are beneficial in a vegetable garden. Spiders prey on all kinds of insects including flies, cucumber beetles, brown marmorated stink bugs, and sometimes even butterflies. Black and yellow garden spiders are not aggressive towards people — although, that does not mean they are not a bit intimidating, especially when you run your face smack dab into the beautiful web while picking tomatoes! 

Orb-weaver spiders spend their days sitting in their perfectly shaped webs, or nearby on the ground, waiting to catch an unassuming insect, which is immobilized, killed, and wrapped in silk to be consumed later. They are most active in the cover of the night and are great additions to your garden!

garden spider web

A black and yellow garden spider makes an orb web about a meter wide. The zigzag silk in the center is called the stabilimentum. Photo: David Cappaert, Bugwood.org

Webs will begin showing up in mid-summer and remain until the first frost. In our high tunnel, they are protected from most of the wind and rain that could normally damage a web. In your yard and garden, look for egg masses in secluded areas that you don’t visit very often, usually located several inches off the ground, maybe camouflaged with tall grass, at the edge of a woods line, or perhaps under bucket rims or plant containers.

spider egg cases in dried grass

Black and yellow garden spider egg mass from the fall of 2019 camouflaged in tall grass. Photo: Ashley Bodkins

As you begin cleaning up your yard or garden this spring, be on the lookout for egg masses of all types and in particular these amazing black and yellow garden spider egg cases. Be forewarned, there are probably hundreds of spiders just waiting to make their exit. From my experience, wherever the spiderlings exit they will live for the next 1-2 years. If you don’t want them in the area where they are located, gently pick up the egg case and move it to an area where they can thrive. 

garden spider is a predatory insect

Embrace the beautiful cycle of life and be ready to capture pictures of some beautiful spiders in your garden this year. All types of spiders are predators and considered beneficial in the garden! Check out more information on spiders on the Home & Garden Information Center website.

This year the University of Maryland Extension Master Gardener Grow It Eat It program is celebrating the little creatures that help us grow what we like to eat! Whether they are pollinating our plants or devouring pests, we couldn’t grow much to eat without the help of beneficial insects and arthropods. Learn more about the Grow It Eat It program. 

By Ashley Bodkins, Senior Agent Associate and Master Gardener Coordinator, Garrett County, Maryland, University of Maryland Extension