What To Sow And Grow In September

September might be peak harvest time, but there’s still plenty to sow and grow this month.

Here's a handy list of what to plant in September, along with the flowers, fruits and vegetables you can grow this month:

Flowers To Sow And Grow

In The Greenhouse/Indoors

• Surface-sow euphorbia seeds now in trays indoors.
• Sow dierama seed now on the surface of moist compost. Keep in a cool greenhouse over winter.

In The Cold Frame / Under Cloches

• Sow calendula seeds in pots now and keep in a cold frame, for fruity colour from early summer next year.
• Sow violas in a cold frame to plant out in the spring.
• Sow lupins, aquilegia, aconitum and hollyhocks in a cold frame now.
•  Sow eryngium and echinops in pots and place in a cold frame this month to enjoy their silvery spiky foliage next year.
• Start verbascum seeds off outdoors now in pots in a cold frame.
• Sow perennial salvias into pots and trays outdoors and leave in a cold frame or unheated greenhouse through the winter.
• Sow red hot pokers into pots and trays outdoors for stunning flowers next summer.
• Sow helenium in a cold frame to attract bees and butterflies into your garden next year.

Direct Sow Outdoors

• Sow Ammi Majous (Bishop's Weed) directly in the ground now where you'd like it to flower. Autumn sowing will produce bigger, more robust plants to grow.
• Sow hardy geraniums outdoors and leave them to over-winter.
• Direct sow hardy annuals, such as cornflowers, poached egg plant, annual poppies and larkspur, for bigger plants next year.
• Sprinkle California poppies into your borders for stunning colour late next spring.
• Direct sow Love-in-a-Mist (nigella) - it will over-winter quite happily and will self-seed prolifically!
• Sow delphiniums this month for flowers next summer.

Plant Outdoors

• Fill gaps in your borders with autumn-flowering plants, such as sedum and chrysanthemum, to extend the colour to the end of the season.
• Plant hyacinth and amaryllis bulbs for forcing, to ensure a crowd of colourful blooms at Christmas. Keep them in a dark, cool place like a shed or garage and bring them indoors when the shoots are 5cm tall. Perfect for a homemade Christmas present!
• Plant spring-flowering bulbs, such as daffodils, crocus and hyacinths.
• Plant out any biennial plants sown earlier in the year. This includes foxgloves, wallflowers and violas.
• Plant new perennials, trees and shrubs. Now is a good time as the soil is still warm and increasing rainfall should be on its way.

Vegetables And Herbs To Sow And Grow

In The Cold Frame/ Greenhouse/ Under Cloches

• Direct sow spinach now and offer cloche protection as the weather cools. This will ensure harvests throughout autumn and winter.
•  Sow spring cabbages, such as 'April' and 'Durham Early' into modules in the greenhouse.
• Sow pak choi under cloches now for an autumn supply of baby salad leaves.

Direct Sow Outdoors

• Sow corn salad (lamb's lettuce) now - it’s a fully hardy crop which can be sown outdoors now for cropping throughout the autumn and winter.
• Sow 'green manures' on empty beds now to help improve your soil structure and prevent weeds establishing over winter.
• Sow 'Hi Keeper' onions into a well-prepared seedbed - these are the best variety of onion for autumn sowing. Only thin your onion seedlings in the spring.
• Direct sow salad leaves now.
• Try sowing the very hardy 'Perpetual' spinach outdoors this month for winter harvests later in the year.
• Sow winter-hardy spring onions, such as 'White Lisbon' and 'Performer' for crops next spring.
• Make your last direct sowings of summer radishes this month - the cooler autumn conditions are ideal.
• Sow turnip seeds into well-prepared beds this September, for small roots.
• Sow winter lettuce, such as 'Arctic King', directly into the ground now.

Plant Outdoors

• Start planting garlic bulbs at the end of the month for cropping next year.
• Plant autumn onion sets this month.
• Plant out any spring cabbages sown during the summer.

Keep One Step Ahead – What To Order This Month

• Order sweet pea seeds to start in cold frames in October.
• Buy in autumn onion sets for an early summer harvest next year.
•  Order rhubarb crowns and asparagus crowns to plant next month.