Direct sowing: carrots, beetroot and salads straight into the ground

01At a glance

• When: once the soil reaches about 7°C. Beetroot and lettuce from late March or April, carrots from April, salad leaves from mid-spring.
• Depth: carrots, lettuce and salad leaves 1cm; beetroot 2.5cm.
• Time: ten minutes a row.
• Kit: a rake, a cane or the corner of a hoe, string, a watering can, labels.

02Wait for warm soil

The RHS puts it plainly: seed won't germinate if the soil is below about 7°C. The date on the packet is a guide, and a cold April beats it every time. The free test is to look at the bed. When weed seedlings start appearing, the soil is warm enough for yours.

Want to start earlier? The RHS suggests February or March for early carrots and late February for bolt-resistant beetroot, but only under cloches or fleece.

03Make the seedbed and the drill

1. 1
   Clear the bed of weeds and stones. Stony ground makes carrots fork.
2. 2
   Fork over anything compacted, then tread recently dug soil lightly so it isn't fluffy.
3. 3
   Rake to a fine tilth. That means a fine, crumbly texture and a flat, level surface.
4. 4
   Mark the row with a taut string.
5. 5
   Draw the drill. Pull a cane or the corner of a hoe along the string to make a shallow groove of the right depth.
6. 6
   Water the drill before you sow. Dampen the base of the groove so moisture sits right where the roots will emerge.
7. 7
   Sow thinly, cover with soil, firm gently and label the row with the name and date.

04Crop by crop

• Carrots: drill 1cm deep, rows 15–30cm apart. Sow April to early July. Thin to 5–7.5cm apart. Ready in about 12–16 weeks.
• Beetroot: drill 2.5cm deep, rows 30cm apart, a seed every 10cm. Sow late March or April to July. The RHS suggests soaking the seed in warm water for an hour first.
• Lettuce: drill 1cm deep, rows 30cm apart. Sow late March to late July. Thin to 15–30cm depending on variety.
• Salad leaves: drill 1cm deep, rows 30cm apart, or scatter over a small patch. Start cutting at about 10cm high.

05Beetroot's odd seed

Each knobbly beetroot "seed" is really a cluster of several. Sow one and you often get a little clump of seedlings. Thin each clump to the strongest seedling once they are about 2.5cm tall, leaving plants 10cm apart. Or do the opposite on purpose: sow two or three clusters together every 15cm and leave them, for bunches of smaller roots.

06Thinning

Thin while seedlings are small, taking out roughly every second or third one until you reach the final spacing. Disturb the ones you are keeping as little as possible. Salad thinnings can be eaten as baby leaves.

Crowded carrots grow twisted. But thinning carrots has a cost, which is the next section.

07Carrot fly basics

Carrot fly larvae feed on the fine roots, then bore into the carrot itself. The egg-laying females find the crop by smell, and the RHS notes they are attracted by the scent released when surplus seedlings are pulled.

• Sow sparsely so you barely need to thin. A pinch of seed goes a long way.
• Cover the crop completely with insect-proof mesh, with the edges buried under at least 5cm of soil. The RHS says a complete covering is more effective than a barrier round the bed.
• Use the calendar. Carrots sown after mid-May miss the first generation of the fly. Carrots lifted before late August miss the second.
• Move the bed each year. The RHS calls rotation essential under mesh. Otherwise flies that overwintered in the soil emerge inside the cover.
• Less susceptible varieties exist. The RHS lists 'Fly Away', 'Maestro', 'Resistafly' and 'Sytan', and is careful to call them less susceptible, not immune.

08Little and often

One long row gives you forty lettuces in the same week. Short rows sown in succession give you salad all summer.

• Lettuce: a short row every fortnight.
• Carrots: every three to four weeks.
• Salad leaves: a small batch every few weeks. Each gives two or three pickings.

The RHS suggests a simple trigger for leafy crops: sow the next batch when the last has about four true leaves. In hot weather lettuce can refuse to germinate. Sow in the evening, water with cold water and give a little shade.

For what to sow once summer turns, see what to sow now for autumn and winter picking.