Deciphering plant tags: annuals, perennials and biennials

Do you remember the first time you went to a garden center? All those colors. All those plants. All those fancy tags with gobbledygook. Help! Plant terminology can vex everyone, even plant geeks. So let me give you the lowdown on some terms that flummox newbies and pros alike.  

The first thing you need to know is that for plants, it’s all about sex. Their number one priority is to make more of themselves. So they are committed to growing robustly to make flowers and seeds. How they get there is different. So we use words like annual, perennial, and biennial. These often confuse folks. Which one do I want? How do they work? What’s the best deal?

It’s all about a plant’s life cycle. Annuals live for a year. Perennials live longer. And biennials take two years to complete their life cycle. Annuals are especially driven to produce seeds because they only have one year to do so. So they push out flowers like mad to make more seeds.

Tithonia – an annual flower. Photo by Marie Bikle.

Annuals’ key selling point: color throughout the growing season. That’s why they are the darlings of container gardens, a blessing for filling gaps and ideal for a sweep of long-lasting color.  

Annuals are less expensive since they last only one season, dying with the first frosts. You can save seeds and replant them, but few do. Some come back from dropped seeds, but that’s rare. 

The downside to annuals is the need to replant them every year. So the cost savings may not be there in the long run and you spend much more time planting. 

In gardens, geraniums, begonias, pansies, marigolds, zinnias, petunias, and snapdragons are commonly treated as annuals.

Perennials are one and done, planted once and persisting for years. Most die to the ground with cold weather, but come back again from their roots, bulbs, or tubers. Most perennials bloom for about a month, but some bloom 2 or 3 times a season if deadheaded. So you don’t get the long flowering time of annuals, but they return year after year.

Perennials cost more but don’t need to be replanted. Plus, they give a different look to your garden throughout the growing season with myriad colors and forms. Perennial gardens have spring, summer, and fall wardrobes. They also are the gift that keeps giving, since you get free plants by dividing perennials every few years. This mitigates their initial higher price tags.  

There are hundreds of perennials including coneflowers, lavender, coral bells, coreopsis, columbine, bee balm, phlox, asters, and goldenrod.  

Biennials flower in their second season. They push out leaves the first year, then flower, make seeds and die in their second year. Hollyhock, foxglove and Sweet William are common biennials. Some biennials reliably reseed so they act like perennials with new plants coming from dropped seeds. Hollyhocks are notorious for rewarding growers year after year.   

I hope I’ve simplified some plant tag terms and made it easier for you to pick what’s right for you – and your gardens – on your next visit to a garden center. 

By Annette Cormany, Principal Agent Associate and Master Gardener Coordinator, Washington County, University of Maryland Extension. This article was previously published by Herald-Mail Media. Read more by Annette.

This article was previously published by Herald-Mail Media.

Spring Ephemerals – The Garden Thyme Podcast

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April is National Garden Month! So Happy National Garden Month everyone. One of the clearest signals of spring is the emergence of spring ephemerals — daffodils, crocus, tulips… these bulbs are some classic examples — but we have so many more to enjoy! Our woodland wildflowers may be more subtle, but are no less impressive and are even more rewarding. This month we take a break from our garden and all the spring chores to talk about some of our favorite woodland spring ephemerals.

Ephemerals covered in this episode include Dutchman’s breeches, Virginia bluebells, mayapples, bellworts, spring beauty, Jack-in-the-pulpit, and pink lady slipper. 

We also have our: 

  • Native Plant of the Month (Sessile trillium) at 22:15
  • Bug of the Month (Termites) at 25:35
  • Garden Tips of the Month at (36:55)

If you have any garden-related questions please email us at UMEGardenPodcast@gmail.com or look us up on Facebook.

The Garden Thyme Podcast is brought to you by the University of Maryland Extension. Hosts are Mikaela Boley, Senior Agent Associate (Talbot County) for Horticulture; Rachel Rhodes, Agent Associate for Horticulture (Queen Anne’s County); and Emily Zobel, Senior Agent Associate for Agriculture (Dorchester County).

Theme Song: By Jason Inc

Improve Soil Health for a Climate-Resilient Garden

Soils, plants, and animals are highly interdependent. Soils support and feed microbes and plants which feed animals. Dead plants and soil critters replenish the soils’ organic matter and nutrient supply, completing the cycle. We know that healthy soils produce healthy plants. Many experts believe that improving soil health is the most important thing we can do to make our farms and gardens more climate-resilient. 

Why are soils so important in dealing with climate change? 

  • They store huge amounts of carbon in the form of carbon dioxide (CO2) and organic matter, all of the living, dead, and decomposing plants, microbes, and animals that live in soil. Carbon dioxide is the primary greenhouse gas that is warming the planet. Deforestation, the removal of wetlands and peatlands, and soil tillage cause the release of huge amounts of CO2. Warmer temperatures cause more rapid organic matter decomposition and turnover, especially if soils are tilled and uncovered.
  • Climate change is causing mid-Atlantic weather to be warmer and wetter with more extreme weather events, including periodic drought. This increases the risk of soil erosion and nutrient run-off from intense rainfall, and the risk of plant stress from excessively wet or dry soils. 
Soil from a landscaping project that moved off-site in 2018. Maryland averaged 73 inches of rain that year!
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Q&A: Why do my hollies and other evergreens have brown and pale leaves?

holly with leaves showing sections of brown and pale color
Winterburn symptoms on holly. Photo: David L. Clement, University of Maryland Extension

Q: Several of our evergreens (different kinds) have brown or pale, bleached-looking leaves. Do they have a disease already, and can anything be done? Is it preventable in the future?

A: Most likely it’s winterburn, especially since most infectious diseases won’t cause symptoms this early and seldom impact several unrelated plants to the same degree. Winterburn is an abiotic disorder or injury – abiotic translates to without (a-) life (biotic) – meaning the condition has a non-living cause. Abiotic plant disorders are environmental, and causes include wind, water, temperature, and soil pH. In comparison, biotic factors would include insects, mites, fungi, or bacteria.

No treatment is recommended because the damage has been done, but winterburn is rarely a serious threat to a plant’s long-term health. As new growth resumes, the plant will eventually shed the damaged leaves. If it’s too much of an eyesore, you can selectively trim away the worst of it this month. Causes for winterburn typically involve a combination of cold temperatures, wind, and exposure to sun. Any autumn pruning that results in tender regrowth is priming a plant for winterburn, which is one reason it’s not recommended.

Why are cold-hardy evergreens damaged? Leaves “breathe” through tiny pores on their surface, and this gas exchange also allows water vapor to leave the leaf. Moisture leaves our bodies the same way – picture foggy breath on a cold day. Breezy days, especially in winter’s drier air, speeds-up this evaporation, as can the sun’s weak warmth. Meanwhile, during cold snaps, moisture in the surface layers of soil freezes, which prevents roots from absorbing it. Since the plant cannot replenish all of the moisture it’s losing, the leaf tissue starts to essentially freeze-dry. A thaw won’t reverse the damage because the cells have been injured, just like skin with frostbite. (Unlike our skin though, which can heal to an extent, leaf tissue can’t repair itself.)

Broadleaf evergreens are more vulnerable to winterburn than needled evergreens because the leaf surface area and evaporation potential is so much greater. Younger plants also have greater vulnerability because they are still establishing roots. This is the main reason it’s risky to plant evergreens late in the fall. Cherry laurel, boxwood, holly, rhododendron, camellia, and southern and sweetbay magnolias are common winterburn victims in our area. Plants kept in containers are also susceptible because their roots dry faster and experience more drastic temperature swings than they would in the ground.

The only actions you can take to minimize winterburn risk is to site evergreens out of the brunt of winter winds and to periodically monitor their root zones for moisture, irrigating when dry during a warm spell. Plants overwintering in pots can be sheltered a bit near a wall or windbreak, but don’t bring them inside as the interruption of dormancy may detriment their health.

Learn more and see additional photos on the Home & Garden Information Center website: Winter Damage on Landscape Plants.

By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun. Read more by Miri.

Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension.

What are local ecotype plants and why do they matter to pollinators?

With the planting season upon us, many of us are starting to think about what flowers may be the best for our gardens and pollinators. We may have started to look into floral mixes or even flower starts, but probably there are too many choices and now we’re overwhelmed and don’t know what to do. In previous posts, we talked about the importance of diverse floral choices and how appropriate native species are when choosing plants for pollinators. There is, however, an extra twist that is becoming more mainstream in this story and today I want to talk about it. Let’s chat about local ecotypes, what they are, what they contribute, and how to get them (and how to not get them).

What are local ecotypes?

In a few words, local ecotypes are native plant species that have a genetic background typical for the local region and adapted to it. I know, there were a lot of technical words in that sentence, so let me break it down to make it easier to understand.

Like all organisms, plants have lineages that reflect their ancestry. In the same way that we as humans are genetically more closely related to members of our own family than to those of other families, plant populations are also more closely related to other plants of the same species that live close to them. From a genetic point of view, this means that plants that come from regions close to each other will tend to have more similar genetic characteristics than those from regions far apart from each other. This genetic makeup specific to a given region is what we call broadly a local genotype.

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Outsmart Squash Vine Borers This Season – Featured Video

Do your squash plants look wilted in the summer? There could be an invisible enemy larva eating your plant stems from the inside out. And worse yet, typically there is more than one miner inside!

This troubling pest, squash vine borer, seems to hit everyone’s garden in the eastern United States! The borer pest is very hard to control since targeting the egg-laying clearwing moth is like throwing darts in the night. Honestly, it is best to plant squash plants at different time intervals to increase your chance of missing the egg-laying time. Early transplant squash can beat out the egg layers and then late season squash can miss them.

Plan your garden accordingly this year, and you may be able to avoid most of the vine borer problems!

HGIC Website: Squash Vine Borers

Joyce Browning Horticulturist, Master Gardener Coordinator Video credit: Bethany Evans Longwood Gardens Professional Gardener Program Alumni; CPH

Grow It Eat It in Montgomery County, May 14

April greetings, and that freeze we had earlier this week was no joke, right? Hope none of your plants got zapped. I was grateful for my own procrastination; my brassica seedlings won’t go into the ground until this weekend.

The uncertain temperatures of early spring make me think longingly of the more settled weather of mid-May (before I start complaining loudly about how hot it is). Another reason to look forward to May: the return of Montgomery County’s big Grow It Eat It open house on May 14!

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