My September Garden

Lisa Hunter • September 13, 2021

Timely tips

Divide your herbaceous perennials. This will keep your plants healthy and vigorous year after year and multiply your stock.
Net ponds now before autumn leaf fall gets underway to reduce the amount of debris entering the water.
Clean out cold frames and greenhouses ahead of autumn sowing and growing.
Plant spring-flowering bulbs now, such as daffodils, crocus and hyacinths

In the flower garden

Continue to feed and deadhead hanging-basket and container annuals — they will often keep going until the first frosts.
Keep deadheading annuals and perennials to extend their performance.
Prune any late-summer flowering shrubs, such as the rock rose
Prune climbing roses and rambling roses once they've finished flowering
Keep camellias and rhododendrons well-watered at this time of year to ensure that next year's buds develop well.

In the vegetable garden

Keep harvesting crops. If you have a glut of fruit and veg try freezing, drying, pickling, and storing so that you can benefit from them later on.
Harvest sweetcorn. To test if it’s ready, pinch a kernel — it will release a milky sap when ripe.
Spread newly dug potatoes out to dry for a few hours before storing them in a cool, dark place. Store them in paper or hessian sacks, as this will allow the crop to breathe while it’s in storage.
Help pumpkins ripen in time for Halloween by removing any leaves shading the fruits.
Raise pumpkins and squashes off the ground to prevent rotting. Place them on a piece of slate or wood.
Keep feeding and watering French and runner beans to keep them producing. Continue harvesting little and often to prevent them setting seed.
Cut bean and pea plants away at ground level when they have finished cropping. Leave the roots which will slowly release nitrogen back into the soil as they break down.
Remove any old crops that have finished and clear away weeds to leave your plot clean and tidy for the winter.
Cover your brassicas with netting to prevent birds making a meal out of them.

In the fruit garden

Tidy up your strawberry plants and clear away any used straw, as this will harbour pests and diseases over winter.
Pot up strawberry runners to make extra plants for next year.
Pick ripe apples. To test when they’re ripe, gently lift them in the palm of your hand or give them a gentle pull — they should come away easily.
Pick off rotting fruits from pear, apple and stone fruit trees — they will spread disease if left on the tree.
Harvest plums. If you have more than you need, freeze them by washing, halving and stoning them, before laying them out on a tray in the freezer. Once frozen, pack them into freezer bags.
Pick blackberries as they ripen and use straight away or freeze some for use later on.
Take hardwood cuttings of currants, gooseberries and figs to increase your stock.

In the greenhouse

Water greenhouse plants early on in the day so the greenhouse is dry by the evening. Damp, cool nights can encourage botrytis.
Close greenhouse vents and doors late in the afternoon to help trap in heat overnight.
Empty pots — old compost and decaying plant material can harbour unwanted pests over winter.
Clean out your greenhouse to reduce the risk of pests and diseases next year.

Looking after your lawn

Create a new lawn from turf or seed — autumn weather is favourable for good lawn establishment.
Raise the height of your mower blades as grass growth slows down.
Carry out essential lawn maintenance to avoid waterlogging and compaction.
Feed your lawn with an autumn fertiliser which is rich in potassium and low in nitrogen.

Other jobs about the garden

Create compost bins in preparation for all the fallen leaves and dead plant material which you'll be collecting over the coming months. Autumn leaves make a great addition to compost bins and are ideal for making leaf mould.
Burn diseased plant material or dispose of it in your household or green waste. Don’t compost it as the spores may remain in the compost and reinfect your plants.
Raise pots off the ground for the winter by using bricks or 'pot feet', to prevent waterlogging.
Clear pond weeds and net your pond in anticipation of autumn leaf fall.
Install water butts to collect rain this autumn and winter. Rainwater is great for watering ericaceous plants such as blueberries, rhododendrons and camellias.