Fast-Growing Vegetables: 8 Quick Crops to Sow Now
Eight fast-growing vegetables you can sow in late summer and harvest in weeks – radishes, salad leaves, spinach and more, with days-to-harvest for European gardens.
There is a particular kind of impatience that every gardener knows: you want something to eat, and you want it soon. The good news is that not every crop makes you wait a whole season. Fast-growing vegetables turn an empty patch of soil into a harvest in weeks rather than months, which makes them perfect for late summer, when the clock is running down toward the first frosts but the soil is still warm enough to push seedlings along quickly.
This list gathers eight of the most reliable quick crops for European gardens, ranked roughly from fastest to slowest. Each entry gives you a realistic days-to-harvest range (cultivar and weather will nudge it either way) and the practical detail that actually decides whether you eat well. Sow a short row every couple of weeks and you will keep the kitchen supplied right through autumn.
1. Radishes: The Classic Three-Week Crop
Radishes are the sprinter of the vegetable garden. Sown directly into moist soil, summer varieties are ready to pull in as little as 20 to 25 days. They ask for almost nothing: a shallow drill, thin sowing so the roots have room, and steady moisture so they swell fast and stay crisp rather than turning woody and hot.
The one rule worth remembering is that radishes bolt and go pithy if they are left too long or allowed to dry out. Sow little and often – a metre of row every ten days – and pull them the moment they reach the size of a large marble. Round red types like French Breakfast crop fastest; longer winter radishes need more patience.
2. Salad Leaves and Cut-and-Come-Again Mixes: 25 to 35 Days
Loose-leaf lettuce and mixed leaf blends are the most generous fast crop you can grow. Instead of waiting for a whole heart to form, you cut the outer leaves at around 25 to 35 days and the plant simply grows more. A single sowing can give you three or four cuts before it tires.
In late summer the trick is a little afternoon shade and reliable water – heat makes lettuce bolt and turn bitter. If you have grown a whole head only to watch it shoot skyward in a heatwave, our guide to why lettuce bolts explains how to keep it sweet. Mustards, rocket, and mizuna add pepper and grow just as quickly.
3. Spinach: A Cool-Season Favourite in 30 to 40 Days
Spinach genuinely prefers the shortening days and cooler nights of late summer, which is exactly why it belongs on this list now rather than in June. Sown from August onward it grows fast, stands well without bolting, and gives you tender leaves in 30 to 40 days.
Pick the outer leaves young and often to keep the plant producing. Spinach that overwinters under a cloche will also give you an early bite next spring, so a late-summer sowing does double duty.
4. Rocket (Arugula): Peppery Leaves in About 30 Days
Rocket is one of the easiest and fastest leaves of all. Salad rocket is ready for a first cut in roughly three to four weeks, and cooler autumn weather makes it milder and less inclined to bolt than a midsummer sowing. Scatter seed thinly, keep it watered, and start cutting young leaves as soon as they are a few centimetres tall.
Wild rocket is slower but hardier and will keep going deep into autumn. Both are happiest sown now rather than at the height of summer heat.
5. Spring Onions: Slim and Ready in 6 to 8 Weeks
Spring onions (scallions) do not need to bulb, which is why they are so much quicker than a full onion. Sown thickly in a row, they are pencil-thick and ready to pull in six to eight weeks. A late-summer sowing crops through autumn, and some hardy types will stand over winter for an early spring harvest.
They are undemanding as long as the soil does not dry out completely. Sow a fresh pinch every few weeks for a steady supply rather than a glut all at once.
6. Baby Turnips: Sweet Roots in 6 to 7 Weeks
Turnips have an unfair reputation, mostly earned by the woody giants left in the ground too long. Pulled young – at golf-ball to tennis-ball size, around six to seven weeks from sowing – they are sweet, tender, and quick. The leafy tops are edible too and cook like spring greens.
Sow direct, thin to about 10 centimetres apart, and keep them growing steadily. Late-summer sowings often taste best because the cooler weather sweetens the roots.
7. Bush Beans (Dwarf French Beans): A Quick Warm Crop in 50 to 60 Days
If your late summer is still warm, a final sowing of dwarf French beans can crop before the frosts. Bush types need no support and produce a concentrated flush of pods in around 50 to 60 days from sowing. This is the tightest gamble on the list – you need a mild autumn – but in Atlantic and Mediterranean climates it usually pays off.
Sow into warm soil, keep the plants watered once they flower, and pick regularly to keep the pods coming. In cooler continental gardens, stick to the leafier crops higher up this list.
8. Kohlrabi: An Underrated Swift Brassica in 7 to 8 Weeks
Kohlrabi is the fast member of the cabbage family. The swollen stem is ready in seven to eight weeks, far quicker than a cabbage or a head of broccoli, and it copes well with cooler autumn conditions. Harvest it at the size of a tennis ball – larger than that and the texture turns fibrous.
Eaten raw it is crisp and mild, somewhere between an apple and a radish; cooked it is sweet and tender. It is one of the most rewarding quick crops for gardeners who want something a little different.
Quick Reference Table
| Vegetable | Days to Harvest | Best For | Difficulty |
|---|---|---|---|
| Radishes | 20–25 | Absolute beginners, edging rows | Very easy |
| Salad leaves | 25–35 | Repeat cutting, containers | Very easy |
| Spinach | 30–40 | Cool-season leaves, overwintering | Easy |
| Rocket | ~30 | Peppery salads, quick fillers | Very easy |
| Spring onions | 42–56 | Flavour, tight spaces | Easy |
| Baby turnips | 42–49 | Roots and greens together | Easy |
| Bush beans | 50–60 | A last warm-season crop | Moderate |
| Kohlrabi | 49–56 | Something different, cool weather | Easy |
How to Choose What to Sow
The right quick crop depends on three things: how much warmth you have left, how much space you can spare, and how you like to eat. In a cool continental garden, lean on the leaves and roots – radishes, spinach, salad, turnips – which shrug off cooler nights. In milder Atlantic or Mediterranean gardens you can still risk a warm crop like bush beans.
The real secret to a well-fed late summer is not planting everything at once but sowing a little every couple of weeks. That rhythm – called succession sowing – turns a single glut into a steady harvest, and it works beautifully with quick crops. Our guide to succession planting shows how to schedule it, and if you want to know exactly when each crop is ready, see our overview of when to harvest vegetables. For the wider late-season picture, our guide on what to plant in September covers the hardier crops that carry the garden into winter.
Sow in short rows, often
A metre of radishes or salad every ten to fourteen days beats one long row sown all at once. You will always have something young and tender to pick, and nothing runs to seed before you can eat it.
Fast-growing vegetables are the easiest way to feel like a productive gardener, whatever the season. They reward attention over patience, they suit small spaces and containers, and they make the most of the weeks that many gardeners write off. Plan a few short rows and you will be eating from your own soil within the month.