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September Tips

The Ornamental Garden

  • September is the beginning of the traditional autumn planting season and is in fact the best time to plant hardy plants. The soil is moist and warm and plants soon get established now, so get out your spades and get planting!
  • Check roses regularly for black spot, mildew and rust fungal diseases. Remove and burn infected leaves and continue regular sprays of Roseclear ultra*.
  • Make sure that any lavender plants, not pruned earlier, are done now. Cut off faded flowers with about 2-3 cm of leaf shoot but don’t cut back into old woody growth. Create a cottage garden effect by sowing easy to grow hardy annuals. Calendula and Love-In-A-Mist [Nigella] look good together. Cornflower, Larkspur and Clarkia will give some height to the middle and back of a border and are good cut flowers too! All can be sown directly into well prepared soil where you want them to flower and don’t need to be raised in trays and transplanted. They are hardy enough to over-winter without frost protection and will give a good show next summer!
  • Check cuttings of Fuchsias, Pelargoniums and other tender perennials for roots. If well rooted, pot them on into 9cm [3.5”] pots filled with good potting compost. If not, leave the potting until spring. There is still time to root more.
  • Cut back early flowering herbaceous perennials close to ground level unless they produce attractive seed heads. The seed heads and some dead stems and leaves can look enchanting with winter ‘hoar’ frost on them.
  • Lift, divide and replant the youngest bits of herbaceous perennials that have finished flowering. Most perennials benefit from dividing every 2-3 years. Improve soil and water in well to get them re-established.
  • Replant pots and hanging baskets with autumn, winter and spring flowering and foliage plants. We have masses of choice! Use fresh compost and Osmocote feed for the best results. We can also plant your basket for you if you wish.
  • Take cuttings of Pelargoniums, Fuchsias and other tender plants.
  • Buy pot feet and put under your outdoor containers so that the pots drain well in winter.
  • Sow fallow areas of your vegetable patch with quick growing ‘green manure’ crop. This will improve the soil structure and reduce nutrients being washed out of your soil by the winter rains. Choose from Winter Tares, Grazing Rye and Field Beans. Dig it all into the soil before they come into flower. (Ask for our Tips on Green Manuring or download from the website)
  • Get compost containers ready for the autumn clean up. Construct extra or perhaps purchase new ones before the leaves start to fall. Shredders are very useful and can turn most trimmings and modest prunings into useful mulching material. Plant shady borders and areas under large shrubs with small flowered Crocus, Scilla, Anemone blanda, Snowdrops and English Bluebells, [don’t plant Spanish bluebells as they may hybridise with our own native bluebells].
  • Try growing a few bulbs, other than the proverbial Hyacinths, in pots for the house. It is much easier than you might imagine! Dwarf Irises aren’t often grown but are very easy if they have good drainage. There are masses of dwarf Tulips and Daffodils to try! Probably the easiest are Tulip ‘Red Riding Hood’ and ‘Pinocchio­’. For Daffodils try ‘Tete a Tete’ or ‘Jet Fire’.
  • Remember to use bulb fibre rather than potting compost if the pots you use have no drainage holes. Make certain that the bulbs have made plenty of roots and that you can feel the flower bud in the shoot protruding out of the bulb before you bring them into warmth.
  • Pot up prepared Hyacinths to get them in flower for Christmas. Get them potted this month unless you are happy to have them in flower in January.
  • Gladioli corms of the non-hardy type (the majority) should be lifted, dried off and stored in a frost free place. The small corms that form around the base are probably best discarded as they can take several years to reach flowering size.
  • Dry off Begonia corms. Cut back and pot up any tender perennials worth keeping in the greenhouse.

The Inside Garden

  • Reduce frequency of watering as days shorten.
  • Any house plants, which are outside for the summer, should be moved back indoors now.
  • Put house plants that like humid air -ferns, bromeliad, insectivorous plants, etc. – on a saucer filled with damp pebbles. Begin misting over the leaves of your plants- especially when your central heating comes back on.

The Kitchen Garden

  • Make the first sowing of Vailan [Winter Gem type] lettuce now. This greenhouse variety can be grown to produce tasty salads right through the winter if sown regularly and given a little heat.
  • Sow Winter Density lettuce [outside] and the winter mix of Speedy Veg leaf salad leaves too.
  • Plant Spring Cabbages in well prepared soil. Space them 30cm [1ft] apart. Apply a fertiliser that has low nitrogen content, the nitrogen can be added in the New Year.
  • Lift root crops such as carrots and beetroot and store them in a frost free place. Bury them in boxes filled with damp sand and keep them in a cool building such as the garage. Setting a mousetrap or two nearby might be a sensible precaution.
  • Lift and store potatoes. They need a frost free, dark cool place.
  • Pick ripe Apples and Pears now. If they come off the tree easily without having to tug hard, then they are ready to harvest. If you cut one or two in half, look for brown pips to show that they are ready. Varieties harvested now will not store well and should be eaten or cooked straight away.
  • Remove and destroy any mummified tree fruits affected by brown rot. This reduces disease spread from year to year.
  • Fix grease bands to tree trunks to trap wingless winter moths that will be climbing the trunks to lay their eggs soon.
  • Plant Garlic cloves now. Light well drained soil suit it best so for heavier soils plant on a ridge of soil that has had plenty of horticultural grit added. Split the bulbs into individual cloves and plant those 20cm [8”] apart.
  • Harvest marrows, squashes and pumpkins before first frosts. Store in a frost-free shed or garage. Cut them leaving an inch or two of stem attached.
  • Harvest sweet corn when the tassels are just going brown and the tops kernels produce milky sap when a thumbnail is pushed into them.
  • Sow the hardy strain of White Lisbon salad onion now. They will over-winter as small plants and provide you with tasty onions for your early spring salads and for flavouring other dishes. They will be ready well before the spring sown ones are ready.
  • Plant winter onion sets and banana shallots for the first crops of next summer.
  • Any trained forms of tree fruits should have the summer pruning completed now.
  • Remove yellowing leaves from the bases of cabbages, cauliflowers, sprouts etc. Sprouts and purple sprouting may need some extra support by staking now.
  • Plant strawberry ‘runners’ (plants). Take care to get the planting depth right! The crown of the plant should be half in and half out of the soil after the soil settles. Try some in grow-bags too.
  • Sow more Land Cress, Mizuna and Lamb’s Lettuce for winter salads.
  • Autumn fruiting Raspberries should be ready to pick and are so easy to grow!

The Wildlife Garden

  • Erect a net over your pond to prevent falling leaves from trees and shrubs getting into the water and increasing the nutrient levels when they breakdown. They may also deprive the fish of oxygen as they decompose.
  • Remove dead leaves from pond plants as they die back.
  • Clean out nesting boxes and give your bird table a good scrub before the main bird feeding season gets underway. Jeyes disinfectant works on bacterial and fungal diseases.
  • Start feeding birds again (if you ever stopped).
  • Provide log piles in odd corners to act as wildlife refuges.
  • Put up lacewing, bee and ladybird shelters to provide over wintering refuges for these very useful predators to stay in your garden.
  • Install a hedgehog, frog and toad shelter.
  • Leave some seed heads and fruits for winter feed.
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