There may be no better starter crop for beginning gardeners than beans. Their ease of germination, relatively low maintenance, and adaptability to nearly any climate make them a cinch to grow. As an added bonus, beans are among the best protein sources in the plant kingdom – you can make a complete meal from just a handful.
Beans are members of the legume family, which convert gaseous nitrogen from the air, unusable by plants, and fix it in soil by way of their roots, with the assistance of bacteria that live in the root nodules. Plants which follow legumes in the garden rotation use the soil-borne nitrogen left behind. This is why beans and all legumes have a nearly universal value as companion plants and cover crops, are superior for restoring weak, depleted soil and are an important addition to your compost pile.
The only real problem, and one I wrestle with every year, is which bean to grow in the garden – there are thousands to choose from (40,000 according to Wikipedia). Here’s a quick primer which may help narrow your choices:
Grow beans for use dried, fresh, shelled, or whole.
Beans are grown for one of two uses: as shell beans, for the actual beans – the seeds – which can be eaten fresh or dried and stored; or as snap beans, which are grown for the pods and eaten whole. The plants grow as vines or bushes and are referred to as runners, half runners, pole, or bush, each having a unique growth habit.
- Pole and runner beans are vines and need support like a trellis or fence. Pole beans will produce until frost, bearing about 3 times as many beans as bush varieties.
- Bush beans grow on… bushes(surprise!) and need no support. Bush beans produce most of their beans in one great flush, which if you’re canning, drying, or freezing large amounts, is perfect.
- Half runners fall between bush and runner beans and are grown mostly in warm regions.
Shell beans or snap beans may grow in any of these habits, so read your seed packet carefully.
When to plant bush beans and pole beans.
Beans should be planted in a sunny area as soon as danger of frost has passed (check your first and last frost dates). Avoid wet soils, as the seeds will rot in place. Once mature, plants produce beans for roughly 4-6 weeks, depending on the variety. Plant seeds every 2 weeks for fresh beans through your first frost.
For pole beans, put your trellis in place before you plant the seeds. Space the seeds ten inches apart and two inches deep along the trellis. You won’t need to tie the bean plants to the trellis like tomatoes, as the vines will easily climb the panel or tower and anchor themselves via their twining stems. Seeds will germinate in about 7 days.
Plant bush beans according to directions on the seed packet, usually one inch deep and 6 inches apart. To create a consistent supply of beans all summer, plant bush beans at three week intervals. Seeds will germinate in about 14 days.
Bean seeds need a soil temperature between 60 and 70 degrees to germinate, and do best with a high percentage of organic matter, so work lots of compost into the garden bed before planting.
After the seeds germinate, maintain even soil moisture but don’t allow the soil to get soggy. Bean plants need one inch of water per week, but pay more attention to even watering when the plants are in bloom. Side dress with compost once per month.
How to “inoculate” beans at planting time.
Beans benefit at planting time from an “inoculation” of a powdered form of soil bacteria known as rhizobia (genus rhizobium). This bacteria forms a symbiotic relationship with legumes, living inside root nodules, consuming carbohydrates from the plant and in turn providing nitrogen which the plant can convert into a usable form. Most soils contain only small amounts of rhizobia, and while your beans will grow and produce without the extra inoculation (especially if you’ve been composting a long time), adding rhizobia at planting time will insure that your plants produce the maximum yield. The cost of the powdered bacteria is minimal, returning many times its investment. Inoculation is especially important in organic gardens, since no synthetic nitrogen fertilizer is added.
When to harvest bush beans and pole beans.
If you like eating beans in the pod, pick them when young and enjoy them raw, stir fried, or steamed (I eat them as I harvest and they’re delectable). Pole beans are usually harvested twice a week and should be picked when they’re pencil thick, when the beans inside are soft and not showing through the pods. Harvesting pods when they’re young also encourages the plants to produce more beans.
If you’re growing beans to save, allow the pods to ripen until they’re brown and the seeds start to rattle inside – the seeds should be hard enough that you can’t bite through them. You can also cut off the yellowed plants at ground level and hang them indoors upside down to dry. Beans stored in airtight jars will last for about three years.
I prefer freezing my leftover snap beans. Simply Canning has excellent information on the proper way to freeze green beans so you can enjoy them in soups and stews over the winter.
By the way, bean vines and foliage are loaded with nitrogen. After harvest, bury the vines and foliage in the garden bed they were grown in or in a bed where you’ll be growing a heavy nitrogen feeder like sweet corn the following season.
Check the University of Illinois Extension for more info on growing and preserving beans.
We garden in Pennsylvania, United States, zone 6B. Much of the info we share is based on gardening in our temperate area. But many of the flowers, vegetables, and fruit we write about can be grown in soil other than ours (clay) and significantly different weather conditions and elevations. You might need to choose specific varieties for your region, modify your garden, add soil amendments, or adjust the soil pH to match our results. Please check your local university extension website for specifics for your area.
Where do you buy rhizobium? I see places on line, but are there any local vendors I can support (and not have to pay for shipping? Thanks, Todd.
Ron: First, check the seed packet – some are pre-treated or include a small packet with the seeds. Most nurseries will have it near the seeds or in the seed racks in spring – I even found it at Lowe’s once. But it goes fast, so buy early.