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September gardening tips

A garden in autumn colours

September’s gardening essentials

  1. Tip 1 Autumn is a great time to plant trees, shrubs, bulbs, perennials and grass seed. Plants that are planted in the autumn enjoy cooler temperatures and ideal growing conditions that allow roots ample time to grow into the surrounding soil.
  2. Tip 2 Add a touch of autumn to your landscape by planting hardy chrysanthemums
  3. Tip 3 Time to feed your plants with a good quality, slow release plant food made for perennials and flowering shrubs and trees that contains slow-release nitrogen, sulphate of potash, iron and other micro-nutrients for overall plant growth and development.
  4. Tip 4 Time to transplant peonies or divide them if you wish to multiply your plants.
  5. Tip 5 Spring blooming bulbs are best to plant in October. Plant Iris, Tulips, Crocus, Daffodils and many others for glorious colour next spring.
  6. Tip 6 September is the best month of the entire year to seed your lawn. This includes both seeding a new lawn and re-seeding an established lawn to make it thicker and healthier.
  7. Tip 7 Autumn is a great time to aerate and/or de-thatch the lawn. If you decide to do one or both of these, they should be done prior to seeding.
  8. Tip 8 Autumn is the best time to feed your lawn with a good quality, slow-release lawn food, with at least two feedings between the months of September, October, November and December.
  9. Tip 9 As mentioned, September is the best month to seed your lawn with improved varieties of quality grass seed.
  10. Tip 10 Time to continue with autumn crops. You can still seed beets, radishes, turnips, and leaf lettuce.
  11. Tip 11 Time to bring houseplants back indoors.
  12. Tip 12 Re-pot pot bound plants with a potting mix.
  13. Tip 13 Fertilise your houseplants a slow release fertiliser.
  14. Tip 14 September is the best time for you to begin creating compost using a compost bin.
  15. Tip 15 Continue to keep weeding, to make sure they cannot compete with other plants for resources. It is suitable to use a kind of weed killer in this month so it can continue to work through the winter.

Week-by-week gardening tips for September

Week 1

  • Sow hardy annuals to be over wintered outdoors and in the greenhouse.
  • Plant out spring-flowering biennials, including forget-me-nots and wallflowers, in their flowering positions to give them time to establish before winter.
  • Plant prepared bulbs for indoor display at Christmas and early next year.
  • Continue to water containers every day if necessary.
  • Plant new border perennials and water the plants in well.
  • It’s beginning to get cold so try to protect your plants as much as you can, water depending on how the weather is.

Week 2

  • Prune deciduous autumn-flowering shrubs over three years old as they finish flowering.
  • Pick apples and pears as they ripen and store the excess.
  • Plant window boxes and pots for winter interest.
  • Apply or renew greasebands on trunks of apple trees.
  • Remove shading wash from the greenhouse if applied in the spring.
  • Sow parsley and chervil for use in late winter and early spring.
  • If you have cabbages ready then be very cautious about insects, they seem to feed on this specific plant.

Week 3

  • Divide and replant large clumps of perennial herbs.
  • Plant bearded, beardless and bulbous irises in prepared sites.
  • Raise the cutting height on lawnmowers as the growth rate of the grass slows.
  • Start to plant sprint-flowering bulbs in borders and in containers, giving priority to daffodils as they begin their root growth earlier than other bulbs.
  • Take pelargonium cuttings to over winter indoors.

Week 4

  • Cover summer bedding with several layers of horticultural fleece if frost is forecast to prolong the display a little longer.
  • Lift tender perennials such as argyranthemums, fuchsias and pelargoniums before the first frost to be over wintered under cover.
  • Scarify the lawn vigorously to remove dead moss and grass then spike if the soil is compacted.
  • If the lawn is in poor condition apply an autumn fertiliser to boost root growth.
  • Give hedges a final trim.