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Think you can’t plant vegetables in late summer? Think again! From hardy spinach to ravishing roots to autumn-planted onions, let’s look at which vegetable seeds to sow while the soil is warm!
If you’ve got empty spaces in your garden beds, scratch some veggie seeds in the ground, pronto! There’s still lots to plant for more harvests once earlier crops are finished. Planting in succession when crops are harvested means that you can squeeze even more homegrown goodness from the space you have. Learn more about planning for succession gardening.
There are other reasons to enjoy late summer/fall gardening. Pests are less frequent and some vegetables actually taste better and are more successful this time of year. Plus, it’s just not as dang hot!
Let’s start with some green—leafy lovelies to keep the salad bowl full on into autumn. Try sowing seeds of a non-hearting or loose-leaf variety of lettuce directly into the prepared ground. If it’s too hot during the day, you may be better off delaying sowing until the evening, when it’s cooled down a bit. A li ttle shade in the form of a plank, netting or shade cloth will be welcome if it’s too hot. See the Lettuce Growing Guide.
To harvest lettuces on into winter, plan to sow a winter - hardy variety in September or so. Ideally, sow the seeds into plug t rays first and then plant them out at their final spacings in raised beds. Plant a foot apart. Once it turns cold, set up my temporary cold frames for those lettuces growing o utside .
Now for some root crops. These should be in – a nd out b efore temperatures take a dive for winter , though some of the roots will happily sit through the winter in milder areas . Sow maincrop carrots, a final sowing of beets or beetroot, some summer radish , and some turnips . Sow all of these seeds direct ly into the ground in a space recently vacated by another crop that’s been pulled.
If you added compost to beds back in the spring, there should be enough nutrients to carry these final crops through the season, but rake in a sprinkling of blood, fish and bone, to give it a little extra boost. Learn more about organic soil amendments.
When you sow carrot seeds, it’s important to sow them thinly which will sa ve time when it comes to thinning seedlings so they are not too crowded. Also, by not thinning, you are avoiding the risk of attracting carrot fly. Thankfully, this late in the summer, carrot fly tend s to be less of an issue .
Give sown carrots a thorough watering and then cover the rows with thick netting. What this will do is keep the soil shaded and cool, helping it stay moist too. Carrots prefer it nice and cool to germinate, so this helps shield the soil from the hot summer sun. This is less of an issue in milder regions but if you experience hot summer s , it’s a vital step!
With carrots, you could harvest the smaller, tender roots quite quickly, but also leave them on to grow on to full - sized carrots to lift as and when needed throughout the winter. See the Carrot Growing Guide.
Sowing beets or beetroot
Beet seeds are nice and chunky. This makes them easier to space out. Interesting fact: Each seed is a seed capsule, so you are likely to get a few seedlings popping up from each one. You can let these grow on as clusters, or if you want especially big beets you may want to thin the seedlings to leave just one at each position. There’s some debate as to which is best. Smaller roots are easier to manage and have a better texture.
The bee ts will be harvested as needed as soon as they reach a good size – from about the size of a golf ball. If the variety is pretty hardy, leave some of the roots where they are, and lift throughout the winter. If a really cold snap is in the forecast, lift all the remaining roots , pack them into breathable boxes of damp sand or old potting mix, and bring them into the outbuilding to protect them.
Next , a row of radish ! Radishes can be unreliable earlier in the season; the lengthening days seem to encourage them to bolt, or flower prematurely. Sowing later in the summer means the days are getting shorter and temperatures will start to cool from the warmest days of midsummer. When you sow radish seeds, you can plant willy - nilly, fitting in here and there where you have space.
Also consider winter radishes like mooli or daikon radish , which will take longer to grow but give bigger, beefier roots that are perfect for cooking with. They have a crunchy texture and a gentle, peppery tang. See the Radish Growing Guide.
Turnips are a beautiful maincrop variety that will start to crop in early aut umn. Again, turnips are less likely to bolt when sown now. A lot of people overlook how amazing turnips are; they give two crops for the effort of one – leafy tops for stir - frying and the roots. Thin to 9 inches apart. The thinnings can be enjoyed, too. See the Turnip Growing Guide to learn how to plant turnips.
Sowing Hardy Vegetables
Some of the hardiest vegetables will sit out the cold months to give a harvest either during the winter or next spring. Some of these vegetables are excellent choices for plugging what we call the “hungry gap” when not much else is growing. Think of these veggies for harvesting next spring:
It’s best to plant seedlings of Swiss chard so grow in plug trays (or buy at a nursery). They can go out in a month or so when you’re digging out all the zucchini to makes efficient use of space. Chard needs wider spacing so they also need their own growing space.
Hardy varieties of spinach can be sown by seed directly into the ground. Spinach will need thinning ; the thinnings will be perfect in salads, then the deep - green mature leaves will be wonderful wilted or steamed for a hit of goodness. Like so many cool - season vegetables, spinach and chard are far less likely to bolt if sown in late summer.
And how about cabbage? If you garden in a hot climate, you will want to germinate cabbage indoors ( inside the house i n the cool of the air conditioning) before very gradually acclimatizing them to outside temperatures —perhaps initially somewhere shaded, before moving them out into their final places. Keep the ground nice and moist and offer additional shade when necessary until the temperatures cool off in autumn.
Now is also the time to sow autumn - planting onions , also sold as Japanese onions, as they were originally bred in Japan . You can start these from seed , sowing into a seedbed to grow on into young plants, which are then dug up and transplanted into their final positions, at their final spacings. Or you could start them from sets (tiny immature bulbs). If you’ve have downy mildew in the past, perhaps skip this crop and try an early - to - mature onion, which is usually ready up to a month earlier than spring - planted onions.
You can also sow winter - hardy salad or green onions now too, which will overwinter to give salad onions next spring.
Finally, don’t forget that late summer’s a great time to be sowing h ardier leafy herbs like cilantro or coriander, and parsley. As with any of our late - season and into - winter crops, remember you can easily extend the growing season by simply covering the plants up – whether that’s with a sturdy row cover, cloches or mini tunnels, or by growing them in a hoop house or greenhouse. That little bit of extra protection can extend the growing period by as much as four weeks , while kicking spring off up to five weeks earlier.
Video: Watch organic gardener Ben as he sows these seeds in late summer for a fall harvest. It’s very helpful to see how it’s all done!
What NOT to sow now
In many regions, it may be too late to sow some of the winter brassicas like kale and hardy sprouting broccoli. However, if you still find young plants for sale that are ready to plant, go for it.
Unless you live in a warmer, southern climate, it would be extraordinarily optimistic to sow warm - season veggies like cucumber, beans and zucchini at this point . They just wouldn’t have enough warmth to really thrive, even if the zukes did hang on in there. This is why each vegetable has pretty specific times of when to sow and plant – you need to take into account all these variables.
Or, the seed packets or online descriptions will tell you exactly how many days it takes for YOUR variety to mature. You can use that number and work backwards from your first fall frost date to see if there is still time to grow in your area.
If it ’s , say, 90 days until your first fall frost date and your seed packet or planting calendar say it’ll take just 75 days to reach maturity – then go ahead and sow it. But as I say, only do this if you r garden gets good, consistent warmth throughout late summer and autumn.
A Final Tip: Select fast - maturing varieties for this time of year!