Growing Lettuce in the Vegetable Plot
Legumes are members of the Leguminosae family. Among vegetables they are represented by various peas and beans, all of which are dwarf or have dwarf forms suitable for smaller gardens. Leguminous plants have nodules on their roots containing bacteria capable of taking up nitrogen from the air.
As a consequence, the roots of legumes are a valuable store of nitrogen and should, where possible, be left in thewhen the plants are harvested and cleared from the plot.
Even in the open, growing lettuce is possible for a good part of the year; with a little protection, it will grow almost all the year round. It is easy to grow and requires little space. The best method is to sow it successionally, a few seeds at a time, every few weeks, so that you have a more or less continuous supply of succulent leaves. If you have severely restricted space the compact varieties recommended will give you a large number of plants from a small area of plot, or they may be grown in tubs.
A recently introduced method of growing produces a large quantity of leaf at the expense of heart; its advantage is that each plant will produce two crops – which represents another space-saving formula. Experiments have shown that the crisp-leaved cos types are the most suitable for this method. From a sowing in early April and successional ones, first until late May and then from August, leaf crops may be harvested from late May to late October.
The following is the method for growing leaf-and-heart lettuce in the normal way. Sow with two or three seeds at each growing point at a depth of 12-20 mm (½-¾ in); thin out to the strongest after germination. The early crops should be sown either in frames or under cloches, the later ones where they are to grow.
The earlies can be transplanted at intervals of 230 mm (9 in) in rows 200 mm (8 in) apart if the plants in alternate rows are staggered; the compact varieties can be packed even closer, at 130 mm (5-1/4 in) and 110 mm (4-1/2 in) respectively. Later crops should be planted at intervals of 300 mm (12 in), with 270 mm (10-1/2 in) between rows.
Successional sowing at one or two-week intervals of a few plants at a time will provide a long season of cropping – provided you select the correct varieties (see list below). An alternative is to sow rows or blocks more thickly than recommended above and then thin them out to the required spacings. If the lifted plants have been gently eased out of the soil, with roots intact, they may be replanted, at the normal spacings, in a new row or block, and will mature later than those left undisturbed.
A good well-drained soil enriched with plenty of compost is required for growing lettuce. Ifis not available use peat mixed with a general fertiliser. A sunny site is best but lettuce may be grown as an early catch crop between rows of later maturing vegetables. Keep watered and weed-free. Over wintering crops will need protection, depending on variety.
The main lettuce pests in a small garden are likely to be leather-jackets, cutworms, slugs, and snails. Aphids may attack overwintering crops, and malathion spray will control these.
Harvest as required, according to variety and sowing date.
Growing Lettuce for Leaves Only
Certain varieties of the normal cos lettuces respond to close-spaced growing by producing leaves and no hearts; two crops may be obtained from each plant, the first being earlier than that obtained by conventional growing methods. Sow at a depth of 12-20 mm (½-¾ in) at intervals of 20-25 mm (¾-1 in) in rows 130 mm (5 in) apart. The sowing programme is as follows: sow weekly for seven consecutive weeks from the beginning of April and for three consecutive weeks from the beginning of August. Soil, site, and cultivation are as for ordinary growing methods; the August sowings may be on ground cleared of the earlier-sown lettuce.
The earlier sowings can be harvested, from the end of. May to the end of August, by cutting the loose heads of leaves off the main stems. These stems, which should be left 20-30 mm (¾ – 1-1/4 in) high, will grow the later crops of leaves from this sowing. Treat the August-sown plants in exactly the same way. Crop them, first from the sown plants and then from the regrowth, from early September to late October.
LARGE CABBAGE: ‘All the Year Round’, for sowing spring to autumn, slow to bolt; ‘Arctic King’, for autumn sowing, medium size, very hardy; ‘Avoncrisp’, for spring and summer sowing, crisp, good quality, resists lettuceand root aphids; ‘Avondefiance’, for spring and summer sowing, softer-leaved than ‘Avoncrisp’, resists and root aphids; ‘Continuity’, for spring to summer sowing, reddish tinged outer leaves; ‘Hilde’ (‘Suzan’), for March-July sowing in the open and for January – February sowing under protection for transplanting in March; ‘Imperial Winter’, for autumn sowing, larger than ‘Arctic King’; ‘Unrivalled’ (‘Trocadero Improved’), for spring to autumn sowing in the open and for January – February sowing under protection for transplanting in March; ‘Webbs Wonderful’, for sowing from early spring onwards, slow to bolt, crisp; ‘Winter Density, for spring to autumn sowing, compact, intermediate between cabbage and cos types
LARGE: cos (all suitable for hearting or leaf-only production) ‘Lobjoits Green Cos’, sown in spring onwards for summer crops and in autumn for spring crops, large, crisp; ‘Paris White’, large, good in hot weather; ‘Valmaine’, medium large
COMPACT VARIETIES: (for growing under cloches or in the open) ‘Little Gem’ (‘Sugar Cos’), for sowing in spring onwards, excellent quality, intermediate between cos and cabbage types; ‘Tom Thumb’, for spring sowing, fine cabbage type
Soil: Rich, well-drained
Sow: Most of the year, depending on varieties
Harvest: Most of the year, depending on varieties