Why Sow in August?
August marks a significant shift in the gardening calendar. While many gardeners are focused on harvesting summer's bounty, it is also a prime time to get certain seeds into the ground. Sowing in August capitalises on lingering warmth and moisture, setting the stage for crops that mature in cooler weather or overwinter for an early spring start. It’s about extending your growing season and ensuring a diverse supply of fresh food and flowers when many summer annuals are fading.
The key to successful August sowing lies in choosing the right varieties. Look for quicker maturing types or those specifically suited to autumn and winter conditions. This allows them enough time to establish before the colder weather truly sets in. By strategically planting now, you can avoid the typical autumn lull in produce availability and enjoy fresh greens, roots, and even some flowers well into the colder months.
This late-season planting strategy not only maximises garden productivity but also offers a chance to prepare for the following spring. Certain hardy vegetables and flowers sown now can overwinter, providing a head start when the growing season resumes. It’s a forward-thinking approach that rewards the diligent gardener with harvests and blooms when they are most appreciated.
August sowing offers a strategic advantage for extending your garden's productivity.
Extending the Harvest Window
The primary benefit of sowing in August is the extension of your harvesting period. Many vegetables that thrive in cooler temperatures can be planted now and will mature before the first hard frosts. This includes a range of leafy greens, root vegetables, and brassicas. By sowing these, you ensure a continuous supply of fresh produce, bridging the gap between summer abundance and the lean months of late autumn and winter. It’s an opportunity to enjoy garden-fresh food for longer than you might otherwise.
Overwintering for Early Spring
Beyond immediate autumn harvests, August is also the time to sow certain crops that will overwinter. These plants, often hardy varieties, establish themselves during the autumn and then lie dormant through winter, ready to shoot away in early spring. This practice can give you an incredibly early start on spring crops, such as certain peas, broad beans, and hardy lettuce, often yielding produce weeks before anything planted in spring. It’s a method favoured by those seeking the earliest possible harvests.
Preparing for Next Year
Some flowers sown in late summer or early autumn can also overwinter, either as small plants or as hardy seeds that germinate the following spring. Sowing hardy annuals like poppies or calendula in August can lead to earlier, more prolific flowering the next year. This practice helps establish strong root systems that can withstand the winter, ensuring a vibrant display come spring. It’s a way of future-proofing your flower beds.
Vegetables to Sow in August
What vegetables can I plant now for a late harvest? August is an excellent month for sowing a variety of vegetables, particularly those that prefer cooler weather or can mature quickly. Focusing on hardy varieties will ensure success. This is your chance to fill gaps left by spent summer crops and plan for a continuous supply.
Leafy Greens for Autumn Salads
Many types of lettuce, spinach, rocket (arugula), and Swiss chard can be sown in August. Look for varieties described as 'cold-tolerant' or 'autumn-maturing'. These will provide fresh leaves for salads and cooking throughout autumn. Sow them successionally every couple of weeks to ensure a steady supply rather than a single glut. These greens are robust enough to withstand slightly cooler temperatures and shorter days.
Key leafy greens to sow include lettuce, spinach, and rocket.
Root Vegetables for Winter Storage
August is the last opportunity to sow many root vegetables that can be harvested in autumn or stored for winter. Carrots (especially faster-maturing varieties), radishes, and beetroot are good candidates. You can also sow turnips and parsnips, although parsnips will require a longer growing season and might be better sown earlier if your climate is very cold. These crops benefit from the residual warmth in the soil to germinate and grow before the ground becomes too cold.
Brassicas for Late Harvests
Hardy brassicas like kale, spring cabbage, and some varieties of broccoli and cauliflower can be sown in August. These are typically sown for overwintering or for a very late autumn harvest. Spring cabbage, for instance, is sown now to grow into a small plant that overwinters and matures the following spring. Brussels sprouts can also be sown, though they require a long season and might be borderline depending on your region's climate.
Other Hardy Options
Don't forget about peas and beans. While most summer beans are finishing, you can sow quick-maturing varieties of peas and broad beans for a late autumn crop. These hardy legumes can often tolerate light frosts. Additionally, herbs like parsley and coriander can be sown now; they often perform better in cooler weather and are less prone to bolting (going to seed) than in the heat of summer.
Sow seeds of quick-growing crops like spinach and radishes in modules or trays if your soil is very wet or cold, then transplant the seedlings once they have a few true leaves to give them a better start.
Flowers and Herbs for Late Colour and Flavour
Your garden doesn't have to lose its colour or flavour as summer ends. August is a surprisingly good month to sow certain flowers and herbs that will provide late-season interest or overwinter for an early start next year.
Hardy Annuals for Autumn Blooms
Many hardy annual flowers can be sown in August. These will grow into small plants that overwinter and bloom the following spring and early summer, often earlier and more profusely than those sown the following spring. Good choices include calendula, poppies (corn or field varieties), cornflowers, nigella, and scabious. Sowing now allows them to establish a strong root system before winter.
Late-sown hardy annuals provide early spring colour.
Winter Plants for Pots
August is also an opportune time to think about container gardening for autumn and winter. While not strictly sowing, it’s when you might start planting out larger specimens. However, for herbs like parsley, chives, and mint, sowing now can still be successful, providing fresh leaves through autumn. For flowers, consider sowing pansies, violas, and wallflowers in trays to grow on and plant into pots or borders later in the autumn.
Herbs to Sow Now
Parsley, coriander, and chervil are excellent herbs to sow in August. They tend to perform better in cooler weather than in the heat of summer. Parsley, especially, is a biennial that can provide leaves throughout autumn and winter if protected. Coriander may bolt less readily in cooler temperatures. These herbs are invaluable for adding fresh flavour to autumn and winter cooking.
Bulbs to Plant Now for Spring
While the focus is on sowing, August is also a key month for planting bulbs that will flower next spring. This includes early-flowering bulbs like crocuses, snowdrops, and winter aconites, as well as later spring bulbs such as tulips, daffodils, and hyacinths. Planting now allows them to establish roots before the ground freezes, ensuring a spectacular display come spring. Although not sowing seeds, it's a critical late-summer planting task.
When to plant spring bulbs? August is ideal for many varieties, ensuring next year's display.
Key Considerations for August Sowing
Success with August sowing hinges on a few critical factors. The weather, soil conditions, and the specific needs of the seeds you're planting all play a part. It’s a different ballgame to spring planting, requiring attention to detail.
Soil Moisture and Temperature
August can still be warm, but soil moisture is paramount. Seeds need consistent moisture to germinate. If your soil is dry, water thoroughly before sowing and keep the area consistently damp until germination. Conversely, in some regions, August can bring heavy downpours. Ensure your sowing areas have good drainage to prevent seeds from rotting. The soil temperature is usually still warm enough for germination, but prolonged wetness can be detrimental.
Ensure consistent soil moisture without waterlogging.
Choosing the Right Varieties
As mentioned, selecting varieties suited for autumn and winter growth is vital. Look for terms like 'cold-tolerant', 'autumn-maturing', 'frost-resistant', or 'overwintering' on seed packets. These descriptions indicate that the plant is bred to perform well in cooler, shorter days. Using standard summer varieties will likely result in disappointment.
Protection from Pests
Young seedlings are vulnerable to pests like slugs, snails, and birds. August can still be an active time for these creatures. Consider using netting, cloches, or organic slug deterrents to protect your precious new growth. Keeping the area around your seedlings clear of debris can also help reduce hiding places for slugs and snails.
Successional Sowing
To avoid a single, overwhelming harvest, practice successional sowing. This involves sowing small batches of seeds every one to three weeks. For crops like lettuce, spinach, and radishes, this ensures a continuous supply of young, tender leaves and roots throughout the autumn. It’s a simple technique that significantly enhances your garden’s productivity over a longer period.
When sowing seeds in August, consider using a cloche or fleece to create a slightly warmer, more sheltered microclimate, which can aid germination and protect young seedlings from sudden temperature drops or heavy rain.