The 5 Seeds You MUST Start in August

We’re at that point in the year when the big harvests are underway, and yet some beds are beginning to look a bit bare. And it’s easy to think: there’s nothing much to sow now, is there?

Wrong! I’m going to show you five crops that grow best when started right now. They’re fast-growing, incredibly rewarding, and will carry on delivering well into autumn and beyond. So let’s not waste another moment – let’s get sowing!

Bok Choy (Pak Choi)

We’re kicking things off with an absolute gem of the late summer garden: bok choy, also known as pak choi. If you’ve grown it before, you already know exactly why it earns the top spot on this month’s list. And if you haven’t, you are in for a treat!

Those plumptious, glossy stems and tender dark green leaves are as beautiful in the garden as they are in a hot wok. Stir-fried with garlic and a good splash of soy sauce, honestly, it’s one of the highlights of the kitchen!

And here’s the genuinely thrilling thing: this is precisely the right moment to sow it. Bok choy is a cool-season crop, which means it positively relishes the shorter days and gentler temperatures that later summer brings. Sow it in the height of summer heat and it tends to bolt (flower and produce seeds) rather than growing those lush, leafy heads we’re after. But sow it now, as temperatures begin to ease off and days begin to shorten, and it absolutely thrives.

I like to sow into plug trays using an all-purpose potting mix. Sow two seeds per plug, then once they’ve germinated, thin them to leave just the strongest seedling in each plug. This approach – starting seedlings in plugs, rather than direct into the ground – also gives the young plants a bit of protection from slugs while they find their feet.

Below is a list of some tiptop varieties to look for. They’re all award winners, whether that’s a prestigious Royal Horticultural Society Award of Garden Merit, or an esteemed All-America Selections Winner. If you’re not sure what to sow, it makes sense to try these as they’ve been chosen for their reliability and performance.

RHS Award of Garden Merit winners

• Baraku
• Choko
• Glacier
• Red Choi
• Summer Breeze

All-America Selection winners

• Asian Delight
• Bopak

Once the seedlings have filled their plugs, usually within three to four weeks, plant them out about 8in (20cm) apart. Keep them well watered, because in dry spells they can become stressed quickly. And do keep an eye out for slugs, which consider bok choy something of a gourmet meal – in fact, it’s one of their favorite things to rasp at. They’ve got excellent taste – I’ll give them that!

Start picking the outer leaves while the plant is still growing, or wait for the whole head to form. Either way, you’ll be rewarded with a harvest that’s quite unlike anything from a supermarket shelf. Super stuff!

Arugula

Next up, arugula. And if there’s one crop that sums up a quick win in the vegetable garden, it’s this one. Arugula is one of the fastest salads you can grow. We’re talking leaves ready to pick in as little as four to six weeks from sowing. It has that wonderful peppery, slightly nutty flavor that transforms a bowl of salad from something ordinary into something with real character and punch. Pile it onto pizza, toss it with pasta, or just eat it straight from the garden – there’s simply no bad way to enjoy it!

This peppery salad belongs to the brassica family – the same family as broccoli and cabbage, and also mustard, which is part of the reason it has that distinctive spicy bite. Its spiciness is in fact a defense mechanism against pests brought about by natural sulfur compounds called glucosinolates. And this peppery tang only intensifies as temperatures drop, which means the leaves you pick in autumn will taste even better than the first flush enjoyed in summer.

Arugula is wonderfully obliging when it comes to where you sow it. Sow it directly into the ground in drills about half an inch (1cm) deep, spacing rows roughly 6in (15cm) apart, then thin seedlings to about 4in (10cm) once they’re up. Alternatively, scatter-sow into containers or deep window boxes for a convenient, at-the-ready supply of patio or balcony leaves.

Sow little and often for a continuous supply. A small row every few weeks will keep things coming along nicely. Water regularly, pick frequently, and if any plants start to flower, cut them back or pull them out and sow afresh. (The flowers are edible by the way, and they make a rather beautiful garnish!)

Turnips

If you’ve grown tough, bitter turnips that have put you off them in the past, now’s the time to try again, because turnips grown at the cooler end of the season are a revelation! They grow fast and become irresistibly sweet and tender, perfect for slicing thinly into salads.

Turnips are a direct-sow crop, meaning they’re best started in the ground where they’ll grow, because they not hugely keen on being transplanted. Make shallow drills about half an inch (1cm) deep, and space rows about a foot (30cm) apart.

Sow the seeds thinly – they’re small but manageable – and cover them over lightly. I very much see turnips as the sister to radishes – they’re both easy to grow and love the same sorts of conditions.

Once the seedlings appear, I’ll thin them in stages until they are about 6in (15cm) apart to give me full-sized roots, though you could leave them a bit closer together if you’d prefer smaller, baby turnips.

The really exciting part is that, sown now, they can be ready to harvest in as little as six to eight weeks. That’s a full, genuinely delicious crop before the season’s done. Roasted in chunks with olive oil and a pinch of thyme, or simply steamed and buttered…they’re outstanding!

Turnip greens, which are just the leafy tops, are also entirely edible and highly nutritious, so even before the roots form you can snip off a few young leaves to add to salads or stir-fries – though just one or two from each plant mind, as we still want those roots.

Chinese Cabbage (Napa Cabbage)

This crop needs a little urgency behind it: Chinese cabbage, also known as napa cabbage or wombok. This is a crop you’ll want to sow as early as possible in our late summer sowing window, as it needs those slightly warmer temperatures to get established before it fully commits to producing its beautiful, dense, pale-green heads.

If you’ve ever made a proper kimchi, or eaten one, you’ll already know how utterly magnificent napa or Chinese cabbage can be. It’s also the base of some of the most extraordinary Asian slaws and braises I have ever tasted. Soft, sweet and mildly peppery, it’s one of those vegetables with enormous culinary versatility.

I start mine off in plug trays. This leafy Asian favorite can be a little prone to bolting if its roots are disturbed, but sowing into plugs and then carefully transplanting while the roots are still relatively young should give it the best possible start.

As with so many seeds I sow into plugs, it’s in with two seeds per plug, which will be thinned to one once they’re up. Keep your plug tray in a bright, sheltered spot. Once again, starting them in plugs helps them get a bit of a head start on those dastardly slugs.

Once the plugs are nicely rooted – usually within two to three weeks – plant them out roughly 12-14in (30-35cm) apart. Napa or Chinese cabbage forms a lovely, tight, upright head and likes a consistently moist soil, so water regularly and, if you can, incorporate plenty of compost into the bed before planting.

Like all brassicas, it’s a favorite of cabbage white butterflies, which lay eggs that hatch into very hungry caterpillars, so covering them with netting is a smart move. It also benefits from growing in a spot with a bit of shade during the hottest part of the day if temperatures are still high where you’re growing. That will reduce any bolting risk quite a bit. I have to say, I reckon napa or Chinese cabbages look a lot like romaine lettuce while they’re young – a hint at their juicy, succulent leaves.

Harvest plants as a whole head once they’re firm and upright, or try the cut-and-come-again method, taking outer leaves as you need them. Either way, it’s a crop that more than earns its place in the late summer and autumn garden.

Cilantro

And now for a herb that polarises opinion like almost no other. You either love cilantro, also known as coriander, with a deep and abiding passion, or you have a very specific genetic quirk that makes it taste like soap – or at least not at all pleasant. If you’re in the first camp, this next section’s for you. If you’re in the second...well, I won’t take it personally!

For cilantro fans, late summer is one of the very best times of year to grow it because it absolutely hates the heat. In summer, it bolts almost immediately – a pinch of seeds today is a flower stem by pretty much next week, or at least it sometimes feels like that.

But as temperatures ease off, cilantro finally settles down and produces those wonderful, aromatic leaves we’re all after. Wonderful in curries, salsas, salads and soups, the flavor is extraordinary.

Cilantro is best sown directly where it’s to grow because it produces a deep taproot that’s sensitive to disturbance, so I sow mine into shallow drills about a quarter inch (0.5cm) deep. Alternatively, you can just scatter the seeds thinly (known as broadcast sowing) to give more of a carpet of cilantro. If the weather is warm, choose a spot that gets a bit of afternoon shade to help keep plants cooler on those warmer days.

Sow little and often – a small batch every couple of weeks – for a continuous supply. Thin the seedlings to about 4-6in (10-15cm) apart once they germinate. Keep the soil consistently moist, and begin picking the outer leaves once the plants are well-established.

One more bonus is that if you do let a few plants flower and set seed (known as coriander seeds in the kitchen even if you call the leaves cilantro), those seeds are a spice in their own right, with a warm, citrusy, slightly earthy flavour that’s entirely different to the leaves. One plant, two completely different culinary ingredients. What’s not to love?

Late summer really is a season of second chances, and every one of what we’ve sown today is going to give us something tasty to pick in a matter of weeks. And you’ll find all the crops featured today in our Garden Planner. Just select a plant, drop it onto your plan, expand it to fit your bed space, and it automatically works out how many you can grow in the area you have. Very smart! Try it out for yourself – for free, no payment details required.

Plants Related to this Article

Bok Choy Grow Guide

Arugula Grow Guide

Chinese Cabbage Grow Guide