garden q&a: select lima variety with care
Q: For the past three years, I have planted a 25- to 30-foot row of limas. My plants are beautiful and there are a lot of flowers on them, but when I harvest, I am lucky to have enough for a few meals — maybe two to three quarts. Can you give me a clue as to what I can do to improve my harvest? There are bees of various types in my garden, and my other plants produce very well.
A: I do have a few suggestions for increasing your lima bean harvest. First and foremost, take care in choosing which variety of lima to grow. Some are well-suited to northern climates like ours, while others are not. Lima beans, in general, prefer more heat than bush beans do, and in a cool growing season, limas will bear very poorly. But, the catch is that they also do not bear well when temperatures are too hot. When we get up into the 90s, limas will sometimes abort their blossoms, shedding them before the pods can develop.
You'll get the best production from your limas when the temperature is consistently in the low to mid 80s. It's certainly not something you can control, but varietal selection does play a role here as some selections are more tolerant of weather fluctuations than others.
My favorite variety is “Fordhook 242.” I much prefer full-sized varieties such as “Fordhook 242” to “baby limas” as I consistently get better production from them. You can get this variety through Johnny's Selected Seeds, www.johnnyseeds.com or 877-564-6697, if you can't find the seeds at your local nursery.
Because limas enjoy hot weather, do not plant them too early in the season. Wait until the soil is at least 75 degrees before sowing the seeds directly into the garden. Work a few inches of organic matter (such as compost or well-aged horse manure) into the planting area a few weeks before seeding, but do not add any extra nitrogen fertilizer as this encourages shoot growth at the expense of flowers and beans. If you had said your plants were not producing many flowers, I would tell you there was probably too much nitrogen in your soil, but since your plants are setting lots of flowers, that is probably not an issue.
That being said, if lots of flowers are present and the temperature remains appropriate for adequate pod set, a different issue could be to blame. Proper pollination may not be taking place. Though you said you see lots of different bees in your garden and all your other plants produce well, inadequate pollination could still be a factor. Be sure to interplant your vegetable garden with lots of flowering plants. A diversity of flowers in the veggie patch increases the diversity of pollinators visiting all the plants there. I recommend adding flowering herbs, as well as annuals such as sweet alyssum, sunflowers, cosmos and the like. The more flowers, the better.
Horticulturist Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio. She is the author of several gardening books, including “Grow Organic” and “Good Bug, Bad Bug.” Her website is www.jessicawalliser.com.
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