Beans talk: the low-down on this magical legume

The low-down on this magical legume

Harvesting dragon tongue beans. Picture: Getty Images

The fairytale of Jack trading the family cow for a handful of magic beans that overnight sprout a beanstalk into the sky has probably inspired a few plantings of bean seeds. Beans are fast growing (but not fairytale fast) and the large seeds are easy to handle, especially for children. They’re a good crop for beginner gardeners, returning a generous harvest for minimal effort.

Beans are warm-season vegetables, sown once the soil reaches 15C; they will crop, in most parts of Australia, until autumn. In tropical and subtropical zones they’re grown from autumn to spring. Worldwide, there are more than 40,000 varieties of beans, derived from Central and South American ancestors, although the choice in Australia is more limited due to our essential biosecurity laws. Beans can be loosely grouped according to whether they’re grown for drying or for eating fresh, as most are better at one than the other.

Dried beans include kidney, borlotti, cannellini, flageolet and haricot beans (which make the familiar tinned baked beans). Many have beautiful colours and patterns, particularly heirloom varieties such as ‘Yin Yang’ and ‘Kilham Goose’. When growing beans for drying, plant them all at once for efficient harvesting, usually in 100-120 days. They’re ready when the pods are dry and the plants die back. Store fully dried beans in an airtight container in a cool, dry spot.

Fresh beans can be called green, French or string beans. They’re fast, cropping in as little as six weeks. Pick pods when tender and sweet, before the seeds inside develop to lumps. Daily harvesting stimulates ongoing production, so the more you pick the more you’ll get.

A runner pole harvest. Picture: iStock

Compact bush or dwarf beans are ideal for pots. At 50-60cm high, they produce beans nearly as tall as the plants. They crop – and finish – more quickly than climbing beans, so keep sowing more plants every few weeks for a longer supply. Varieties include ‘Bonaparte’ (dwarf French, get it?), ‘Tendergreen’ and the heirloom variety ‘Sex Without Strings’. Climbing varieties produce three times the yield, over a longer period, than the bush types and tolerate humid conditions better. However, they need a supporting trellis on a wall or fence, or a teepee of tall stakes to climb on.

There are flat and rounded pods, stringless or not, and of course they’re not just green. ‘Purple King’ has purple flowers and velvety purple pods, yellow varieties are often called butter beans, while ‘Dragon’s Tongue’ has purple and lemon streaked pods. Among green beans, popular varieties are ‘Blue Lake’ and the heirloom ‘Lazy Housewife’. Snake beans, which are from a different genus, cope best with heat and humidity, bearing extraordinarily long, thin pods that stay crunchy when cooked.

Some beans are perennials rather than annuals. ‘Scarlet Runner’ is an heirloom variety with bright red flowers that reshoots each spring. It prefers cool conditions and may not set pods in warm climates. Lima or Madagascar beans, suited to the tropics, crop in flushes over a three- or four-year period. Other bean types to explore include winged, adzuki, mung, tepary and soybeans.

Good to know:

Climbing beans are highly productive in small spaces because they grow up, not out. Use the light shade beneath them to grow lettuces. Beans like a pH of 6-6.5 and are not frost tolerant. Sow seeds directly where they are to grow. Although self-pollinating, the flowers are still attractive to bees. Save seeds from your best plants, letting some pods mature and dry at the end of the season. Heirloom and organic seed suppliers include greenharvest.com.au, diggers.com.au, greenpatchseeds.com.au and edenseeds.com.au.

Q&A

Is it true that the dreadful, persistent smoke last summer caused the profuse flowering we’ve had on camellias and azaleas? Should I leave the fallen camellia blooms on the ground as mulch? David Ritchie, Canberra

Smoke triggers seed germination and flowering of some native species but would not make camellias or azaleas bloom. Good rains at bud formation time would. Fallen blooms are a natural mulch that will return organic matter and nutrients to the soil; alternatively, add them to the compost heap.

Should I cut off the spent flower spike on my Gymea lily? I did this to a previous plant and it’s never flowered again. Jennifer Simon, Melbourne

You can cut old flower spikes at the base unless you want to collect the seeds. According to native plant expert Angus Stewart, each plant flowers once then gradually dies. This stimulates new plants to grow at its base, which flower in turn. In the wild, bushfires trigger flowering. Gymea lilies respond well to slow-release fertiliser.

What do I do with my tulip and daffodil bulbs over summer? I have a lot in pots, but want to plant and leave them in my new garden. When should I do this? Shar Ramamurthy, Melbourne

Plant the daffodils out after flowering and apply liquid fertiliser until the leaves start to die down; they might take an extra year to flower again, but should then keep blooming. However, tulips need winter chilling to form flowers, so are usually lifted once the foliage dies off, stored in a cool, dark, dry place, then chilled for six to eight weeks in the refrigerator before replanting.

Send your questions to: [e-mail] or Helen Young, PO Box 3098, Willoughby North, NSW 2068. Website: helenyoung.com.au. The best question for October wins Wallgarden’s Multi-hang Vertical Garden Kit with 20 modules, worth $138. September’s winner is Kate Brooking of Adelaide for her question about using honey.