15 garden tips for September

September’s a beautiful month in the garden, with plenty of colour from autumn leaves and late-flowering plants. It’s time to harvest the last of the summer crops and tidy up the beds to be ready for winter. Here are our top 15 gardening tips for September:

15 September’s gardening tips

  1. As strawberry plants put out runners (long stems with clusters of leaves), peg down the leaf clusters on the soil where they will root and form new plants. If you don’t want new plants, cut off the runners to conserve the mother plant’s energy.
  2. Maincrop potatoes should be ready to harvest this month. Cut down the foliage, leave it for three weeks and then dig up the potatoes – kids will love doing this! Leave the potatoes to dry for a few hours, then store them in hessian sacks or paper bags in a cool dark place.
  3. Pinch out the growing tips of cordon tomatoes once they have produced seven trusses so they can focus all their energies on ripening the fruit.
  4. Once you’ve picked the last of your French and runner beans, cut the plants down to ground level and leave the roots in the ground to release their stored nitrogen.
  5. Prune summer raspberries. Cut back all fruited canes to ground level and tie in new canes to support in preparation for next year’s fruit.
  6. Harvest plums, pears, apples, blackberries, and autumn raspberries in the orchard.
  7. Get a head start on next year’s veg crop. Sow spinach and spring onions for next year and cover the seedlings with fleece to protect them from frost damage. Plant autumn-sowing onion and garlic sets for early harvests. Onion ‘Electric’, onion ‘Radar’, garlic ‘Germidour’, and garlic ‘Picardy Wight’ are all ideal for autumn planting. 
  8. Direct sow hardy annuals like poppies, cornflowers and nigella outdoors for early flowers next summer.
  9. Plant out wallflowers and other biennials to give them time to settle in before winter.
  10. Keep deadheading dahlias and roses for a last flush of autumn colour.
  11. Cut back faded perennials. Now’s a good time to lift and divide geraniums, hostas and other perennials, reducing overgrown clumps and giving you extra plants!
  12. Plant new perennials while the soil is still warm from the summer. The autumn rains will help to keep them watered.
  13. It’s time to plant spring bulbs like daffodils, crocuses, alliums and irises. Wait until November to plant tulips, as they’re less at risk from viruses once the weather is colder. 
  14. Do your autumn lawn maintenance. Scarify and aerate the lawn, and give it an autumn feed high in potassium to harden the grass, ready for the cold winter weather.
  15. Water camellias and rhododendrons regularly, as they are now developing the buds for next year’s flowers.

Whether you’re planting, pruning or harvesting, you’ll find everything you need in our centre. Come in and see our fantastic range of plants, tools and garden equipment!

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