Gadenin日本語Get the appTwo windows, two different crops
Beetroot is not really one crop grown at different times; the spring sowing and the late summer sowing behave differently enough to plan separately. The spring crop is sown into soil that is only just warm, grows into lengthening days and rising heat, and carries a real risk of bolting. The late summer crop is sown into warm soil, germinates in under a week, and grows into cooling, shortening days, which is exactly what beetroot prefers.
If you have had trouble with beetroot, the late summer sowing is the one to concentrate on. It almost never bolts, the roots hold their quality longer in cooling soil, and there is far less pest pressure. Reserve the spring sowing for the pleasure of an early crop and accept that some of it may run to seed.
Between the two, high summer is the weakest sowing window. Soil above 86F (30C) germinates the seed erratically, and roots that swell in real heat go woody at a smaller size.
| Sowing window | Soil condition | What you get | Main risk |
|---|---|---|---|
| Early spring, under cover | Cold, protected | The earliest baby beets | Bolting from cold |
| Mid to late spring | Above 50F (10C) | Main summer crop | Bolting, drought in early summer |
| High summer | Often above 86F (30C) | Patchy, small roots | Poor germination, woody flesh |
| Late summer to early autumn | Warm and falling | The best quality main crop | Running out of season if sown late |
The spring crop, stage by stage
A spring sowing takes roughly ten to twelve weeks from seed to a tennis ball sized root, longer if the early weeks are cold. The critical decisions are all in the first month: when you sow relative to soil temperature, and whether you thin on time.
| Stage | Timing from sowing | What you do |
|---|---|---|
| Sowing | Week 0 | Soak seed overnight, sow half an inch (1 cm) deep into damp soil |
| Emergence | Week 1 to 3 | Keep the surface damp; protect from birds and slugs |
| First thinning | Week 3 to 4 | Reduce each cluster to two seedlings at the two leaf stage |
| Second thinning | Week 5 to 6 | Final spacing of 4 in (10 cm); eat the thinnings |
| Roots visible | Week 6 to 8 | Mulch, water an inch (25 mm) a week, hand weed only |
| First harvest | Week 8 to 10 | Lift at golf ball size for baby beets |
| Main harvest | Week 10 to 14 | Lift at 2 to 3 in (5 to 8 cm); do not let them oversize |
If a cold spell is forecast in the first month, cover the row with row cover. Two weeks below 50F (10C) on young plants is what sets up the bolting you will see six weeks later.
The late summer crop
Sown as the peak heat starts to break, beetroot germinates in five to seven days and grows quickly through the warm early weeks, then slows and sweetens as the nights cool. The roots hold their condition in cool soil far longer than a summer crop does, which is why this sowing is the one to store from.
The one thing to get right is the sowing date. Count back roughly ten weeks from your first hard frost and sow no later than that. Sown too late, the plants sit at half size through the cold and never fill out. Sown on time, they reach size just as the weather turns and you can hold them in the ground for weeks.
- Count back ten weeks from the first hard frost That is your last safe sowing date. Anything after it is a gamble on a mild autumn, and half grown roots do not improve over winter.
- Shade the bed if the soil is still hot If the surface is above 86F (30C), lay shade netting or a board over the drill until the seedlings break through, then remove it immediately.
- Thin quickly, the plants move fast In warm soil a late summer sowing reaches the two leaf stage in under two weeks. Thin on schedule or the clusters lock together while you are still thinking about it.
- Mulch as the roots start to show A straw mulch evens out the moisture as autumn rain arrives, and later becomes the insulation that lets you leave roots in the ground.
- Decide before the first hard frost Either mulch deeply and leave the roots in the ground to lift as needed, or lift the lot and box them in damp sand. A frozen beetroot goes soft when it thaws.
Sowing in succession
Beetroot has a short window at its best size, roughly two to three weeks before the flesh starts to coarsen. A single big sowing therefore gives you far more beetroot than you can use at once, followed by a bed of woody roots. The answer is a short row every two to three weeks rather than one long row.
A practical pattern is a three foot (1 m) row every three weeks from the point the soil warms in spring until high summer, then pausing through the hottest spell, then resuming for two or three sowings from late summer. That gives a continuous supply of roots at the right size instead of a glut and a gap.
| Sowing | When | Purpose |
|---|---|---|
| First | As soon as soil is above 50F (10C) | Early baby beets; use bolt resistant seed |
| Second and third | Every 3 weeks through spring | Main summer supply |
| Pause | Peak heat | Germination is unreliable and roots coarsen |
| Fourth | As the heat breaks | The best quality crop of the year |
| Fifth | 10 weeks before first hard frost | Roots to store or leave in the ground |
Multi-sown clumps grown in modules are useful for filling an awkward gap in the succession, because they can be planted out at four weeks old wherever a bed has just been cleared.
Where beetroot sits in the rotation
Beetroot follows a heavily fed crop rather than being fed itself. Ground manured for beans, squash or brassicas the previous season is ideal: there is plenty of organic matter to hold moisture, but the nitrogen has been used up, which is exactly what stops the crop from making all leaf and no root.
Leave three years before beetroot returns to the same bed, and count chard, spinach beet and any other beet as the same crop for that purpose. They share leaf miner, leaf spot and the same soil borne problems. Beetroot is also a useful catch crop, quick enough to fit between a spring crop coming out and a winter one going in.
The notes that make next year easier
Beetroot rewards record keeping more than most crops because the important events are all invisible until it is too late to act. Write down the sowing date and the soil temperature at sowing, the date of emergence, the date you finished thinning, and the date and diameter at first harvest. Note any plant that bolted and how early it was sown.
After a single season those notes give you your own garden's growing period rather than a generic figure, and after two you will know exactly how early you can risk sowing before bolting starts. Add the position of each row on a simple sketch of the beds and the three year rotation looks after itself.