How to grow shallots

Shallots can be started from seed, but are more usually grown from sets (immature bulbs). Each set produces a cluster of new bulbs, whereas a seed produces just one. Sets are the easier option, and are quicker to grow, fare better in colder regions and tend to be less vulnerable to disease. However, they are more expensive and must be planted soon after buying. Choose heat-treated sets to reduce the risk of bolting (flowering).
 
Seeds, on the other hand, are usually cheaper to buy and a packet could last several years. Seed-raised plants are less likely to bolt, but grow more slowly and need more attention in the early stages.

Shallot come in various shapes, including rounded, teardrop and torpedo (or banana) types

Shallot sets are available in autumn and spring in garden centres and from online retailers. Seeds are usually available from similar sources all year round. You may also find young plants on sale in garden centres in spring and early summer, ready for planting out – ideal if you only want a few.

Sow shallot seeds in late winter in modular trays or small pots. Sow five or six in each module/pot, then thin out to three or four seedlings. Each seed will only produce one bulb, so sowing several together will produce a clump. Seeds need 10–16°C (50–60°F) to germinate. Keep the seedlings in a warm bright place – they can be transplanted outside in spring – see Planting below.

Sow shallot seeds from early to mid-spring outdoors, once the soil is drier and beginning to warm up. Prepare the sowing site as described above. Sow the seeds thinly, in drills 1cm (½in) deep, spacing rows 20cm (8in) apart. Protect the seedlings from slugs and snails, especially in damp weather. Thin out the seedlings first to 5cm (2in) apart, then later to 10cm (4in). Closer spacing will result in more bulbs and a heavier overall crop, but smaller individual bulbs.

Once well rooted in, shallots don’t generally need watering except in prolonged dry spells in early summer or if growing in a container. Avoid watering once the bulbs have swollen in mid-summer. Watering spring-planted crops after mid-summer can mean they store less successfully. Also try to avoid wetting the bulbs or foliage if you do water, as this can encourage fungal diseases.

In late winter, give autumn-planted shallots a nitrogen-rich fertiliser, such as sulphate of ammonia, at a rate of 35g (1oz) per square metre/yard, or use a dry poultry manure. This not only improves growth but can also deter premature flowering (bolting). You can also give an occasional feed with a general liquid fertiliser, from spring to mid-summer, especially if plants are in containers.

For a good crop of shallots, it’s important to keep weeds at bay. Shallot leaves cast little shade, so weeds grow readily and can soon swamp the crop, leading to poor growth and smaller bulbs. So weed regularly, ideally by hand. If using a hoe, be careful not to damage the bulbs or foliage. Planting through a biodegradable weed-suppressing membrane (see Planting, above) reduces the need for weeding. 

Remove any flower stems as soon as they start to form, otherwise the plant’s energy will go into producing the flower, rather than swelling the bulbs. It also means the bulbs won’t store well, so at harvest time set aside any that tried to flower, to use first.