Tips for Growing Bush Beans
Super bush beans are a snap to grow if you play the game right. That's not just idle talk, but the opinion of a man who's spent his life studying this humble legume. Buy the best seed, give it the right conditions in which to sprout and grow, and plant multiple crops. That's all there is to it, says this expert.
Dr. Nathan Peck comes from a farm family in New York State's Finger Lakes region, but unlike early generations in his family, he took a different path, attending nearby Cornell University to study plants rather than merely grow them. His father was hesitant at first. "He couldn't see why I had to go to college to learn to farm," Peck relates, "but in the end it turned out pretty well."
Peck earned a bachelor's degree in Plant Physiology, a doctorate in Soil Physics, spent three years working as a research agronomist, then came home to take a professorship at Cornell. For the next 30 years, he studied beans. Retired in 1989, he lives on the land that has been in his family since 1825 and tends a landscape that includes not only flower beds and a rock garden, but a large vegetable garden full of, you guessed it -- beans.
Fresh Seed is Best
"Seed quality is the number one problem for the home gardener," Peck maintains. "Buy new seed every year, and keep it in a cool (below 50oF) dry place until planting time. Bean seeds are very fragile, very sensitive; they can deteriorate very rapidly."
Once they are in the ground and starting to sprout, though, bean seeds are still susceptible to various problems. "They've got big cotyledons (seed leaves) and sometimes half of them will just crack off, or the embryo breaks off and doesn't develop," Peck explains. "Beans are big, lousy seeds -- not like corn, where you can get 98% of the seed to produce a good plant -- and everything likes them: the bugs, the diseases, all that." He recommends a seeding rate of eight to 10 seeds per foot of row. "That's going to give you four to five good, productive plants. Early in the season, I'd plant a few extra seeds, and then when conditions are better, fewer because you'll have better survival rate."
He plants his first crop a week or so before the frost free date (MAY 10 in central New York), using a quick-maturing variety. "There's a 50% chance you'll lose it, but if you do get a crop you'll have bragging rights for sure. And if you don't, you'll have more beans coming right along." Some good varieties to try for the early crop are Contender Earliserve and Topcrop.
Peck's choice for later crops is Bush Blue Lake 274 for its combination of quality and productivity, but he stresses that this is just a personal preference. Other good varieties include Provider, Tendergreen and Bush Kentucky Wonder. For a large, flavorful part-Romano type, try Jumbo.
Once he starts planting, Peck continues seeding a new crop every seven to 10 days up to 60 days before the first fall frost. "Just as soon as you see the plants coming up, it's time to plant more seed," he says. "Not too much; ten feet, maybe even six feet. You'll get lots of beans."
Planting depth depends on soil conditions and the season. "Beans will not tolerate wet soil or cold soil. If the soil is heavy, ridge it up for the first plantings -- three or four inches, even five or six inches -- then plant the beans one inch deep in the top. When the sun comes out it will warm that ridged soil right up. (Sandy soils can be planted almost anytime once they're warm enough, at least 50o to 55oF.) In the summertime, however, the soil gets dry, so plant bean seeds two inches deep to get them down into the moisture."
Nathan Peck spent the majority of his research time studying the effects of fertilizers on snap beans and presenting his findings to agricultural groups. "I've got 115 articles to my credit," he told me (only after persistent questioning, as he is an overly modest man), "and have probably given more talks about snap beans and fertilizer than anybody, bar none." Yet his advice to home gardeners about fertilizing beans is: don't -- unless you really have to -- and if you do, be very cautious. Why? "With home gardeners, I'm afraid they're going to use too much. I've seen more injury from too much fertilizer than I have from not enough. Whatever the recommendations say, put half that amount on. The most you should apply is a pound per hundred square feet of, say, 10-20-10." (In terms of actual nutrients, that's one tenth pound each of nitrogen and potassium and one-fifth pound of phosphorus.) "Beans are legumes, so they don't really need the nitrogen -- they'll grow too many leaves, and not enough pods. Phosphorus is great for seedling emergence, seedling growth, blossoms and pod set; potassium is good for root development, and the high phosphorus requires the potassium to maintain a balance." If you do use this fertilizer, it should be applied at least two weeks before planting, and worked thoroughly into the soil. But Peck does it a little differently. "I put the fertilizer on in the fall when I plant a cover crop of annual rye or ryegrass. The cover crop will take it up. Then I work the cover crop in with a rototiller in the spring and forget the fertilizer. The home gardener can pretty much forget minor elements, too; the cover crop should take care of those." If the cover crop is alive and growing when it is turned under, be sure to wait two to three weeks before planting so it has time to break down.
Peck also doesn't see the need for inoculating the seed with rhizobia. "Sure, if you haven't planted anything in that area before, it won't do any harm," he says. "But the bacteria stay in the soil for years, so if you have ever grown beans there, it's likely that there are plenty of bacteria around."
Pick Plants, Not Pods
If you've followed the rules up to this point, in 50 to 60 days you'll be ready to harvest. Harvest, not pick. "I don't pick beans -- too much bending over. I pull the plants as I go, harvest the pods, and then throw the plants on the compost pile. If you pick some early and some late, the last of one crop will be gone just as the next is ready. You can get a week's harvest out of each planting. And if one planting fails, you're not through. Harvesting is even easier is you use a top-bearing variety like Derby, or hold the plants upside down to harvest, so the beans hang free of foliage." Follow the Peck plan and you'll have a steady stream of beans through the season.
Shepherd Ogden is president of The Cook's Garden, a mail-order seed business in Londonderry, Vermont, and author of Step by Step Organic Vegetable Gardening (HarperCollins, New York, 1992).