How do you know which annuals will do well in your garden?

Annuals are so tempting in the garden center, all lined up in neat rows. To help make good choices, check out the research that’s been done in your area’s test gardens.

In my work as a landscaper, I’m responsible for choosing a fair number of annuals that are planted in clients’ gardens. And when the plants fail to perform, they look to me. So, who do I look to?

Choosing annuals is tricky because you can’t rely on the catalog photos or the plant tags. They always look spectacular. When it comes time to fill your cart with little plastic pots and six-packs, it’s hard to make good choices because everything looks so good. What’s more, growers are likely to choose plants that are “showing color” early because folks are less likely to buy plants that are not in bloom yet.

If you want to make smart choices, do a little research — or take advantage of the work done by someone else. In addition to my own trial-and-error, I look to reports prepared by the local university. They do trials every year, featuring the All-America Selections. I can see them in the park downtown — and read their reports online. What is an “All-America Selection”? These are flowers and vegetables that have been tested by a network of independent judges who say the varieties have “superior” performance.

But what’s “superior” in San Francisco might be “disappointing” in Denver. That’s why these local tests are so valuable. They give you a better idea of how the top annuals perform in your area. For instance, I saw some new begonia cultivars in a catalog. They looked fabulous, but local tests give them a ranking of “d”, which means dead. Oh, I’ll still try a few, but I won’t do a major planting for a key client.

Keep in mind that in some cases, the failure can be blamed on the weather. Last year’s testers noted that last July was wetter than normal. Sometimes it’s just bad luck. The key is this: Get information from a variety of sources, such as the local test garden or your neighbor down the street. To find out what kind of testing is going on in your area, go to the All-America Selections site and/or check with your state cooperative extension system.

Diamond Frost euphorbia

Diamond Frost, a type of euphorbia from Proven Winners.

Based on 2008 test results, here are some of the winners in my area. All of them are on my shopping list for 2009:

  • Bidens ‘Solaire Yellow’
  • Celosia ‘Chinatown’
  • Coleus ‘ColorBlaze Sedona’
  • Euphorbia ‘Diamond Frost’
  • Portulaca ‘Yubi Apricot’
  • Zinnia ‘Magellan Coral’

David Grist, Online Content Coordinator, Gardener’s Supply