Ask a Garden Designer: What to Do in the Garden in September
September is the month that offers a glimpse of the wonderful autumn colours to come. It’s also a very busy time in the garden…
As the nights start to draw in and the morning dew becomes heavier, the garden has a hint of autumn about it, but this month is one of the busiest in the gardening calendar. The abundance of apples, pears and vegetables heralds gathering the harvest and storing the produce for the winter months, and it’s also time to plant bulbs for a colourful display next year.
Harvest with care
Continue to harvest fruit as it ripens on the trees and bushes. Some varieties won’t be ready until October, but for fruits that are, handle carefully so as not to bruise them, which affects their storage qualities.
Don’t store blemished fruit. Apples are best wrapped separately in old newspaper and laid on slatted trays in single layers. Pears are better left unwrapped. Watch out for wasps on damaged fruit so you don’t get a nasty surprise!
Autumn fruiting raspberries will be ready at the end of the month. Once you’ve picked them, don’t prune the canes until late winter or early spring.
Continue to harvest fruit as it ripens on the trees and bushes. Some varieties won’t be ready until October, but for fruits that are, handle carefully so as not to bruise them, which affects their storage qualities.
Don’t store blemished fruit. Apples are best wrapped separately in old newspaper and laid on slatted trays in single layers. Pears are better left unwrapped. Watch out for wasps on damaged fruit so you don’t get a nasty surprise!
Autumn fruiting raspberries will be ready at the end of the month. Once you’ve picked them, don’t prune the canes until late winter or early spring.
Plant spring bulbs
This is the month for planting bulbs to flower next year – apart from tulips, which are best left until November.
Try planting some different bulbs, such as ornithogalum, a lovely white star-shaped flower edged in green, or the beautiful small bright blue scilla, which looks wonderful en masse, as does grape hyacinth (muscari).
Bulbs look particularly good naturalising in grass. To get an informal drift, scatter them across an area and plant them where they land, at two to three times their own depth.
Don’t forget that some spring plants are grown instead from corms, including, for example, Anemone Blanda. You’ll need to remember where you plant them, as they can look like small pieces of shrivelled up soil initially – easy to dig up accidentally!
This is the month for planting bulbs to flower next year – apart from tulips, which are best left until November.
Try planting some different bulbs, such as ornithogalum, a lovely white star-shaped flower edged in green, or the beautiful small bright blue scilla, which looks wonderful en masse, as does grape hyacinth (muscari).
Bulbs look particularly good naturalising in grass. To get an informal drift, scatter them across an area and plant them where they land, at two to three times their own depth.
Don’t forget that some spring plants are grown instead from corms, including, for example, Anemone Blanda. You’ll need to remember where you plant them, as they can look like small pieces of shrivelled up soil initially – easy to dig up accidentally!
Air your lawn
Mowing will become less frequent from now on and, at the end of the month, lawn work should start by first removing any thatch or dead grass that has built up over time. Leaving it will restrict any air movement and cause drainage issues as well as moss and weed growth. You can use a spring rake to drag it off or a powered lawn scarifier (which removes lawn cuttings and moss, and cuts through turf) for bigger areas. The lawn will look a mess for a while, but will soon recover.
After this you can aerate the lawn by pushing in a fork about 6in at 6-9in intervals. Follow this with a top dressing – a mixture of sieved garden soil, sharp sand and sieved garden compost. You can add grass seed if the lawn is a bit worn.
Explore some gorgeous ways to go grass-free
Mowing will become less frequent from now on and, at the end of the month, lawn work should start by first removing any thatch or dead grass that has built up over time. Leaving it will restrict any air movement and cause drainage issues as well as moss and weed growth. You can use a spring rake to drag it off or a powered lawn scarifier (which removes lawn cuttings and moss, and cuts through turf) for bigger areas. The lawn will look a mess for a while, but will soon recover.
After this you can aerate the lawn by pushing in a fork about 6in at 6-9in intervals. Follow this with a top dressing – a mixture of sieved garden soil, sharp sand and sieved garden compost. You can add grass seed if the lawn is a bit worn.
Explore some gorgeous ways to go grass-free
Tend to perennials
Here are three things to do for perennials this month.
1 Keep deadheading them to prolong flowering. Plants such as penstemons, dahlias and delphiniums need to be regularly deadheaded, and you will be rewarded with new blooms for many weeks to come.
2 Plant new perennials, as the soil is still warm and moist enough for the roots to get established before winter. Give new plants a good soak before planting and mulch around them when planted to keep moisture in the soil.
3 Divide clumps of perennials that are becoming old and bare in the centre. Use two forks if you can and prise through the clumps, pulling them apart gently. Trim off excess foliage and replant new, smaller clumps in soil that has been well prepared with organic matter. Groups of three or five look best – and make sure you water well.
Here are three things to do for perennials this month.
1 Keep deadheading them to prolong flowering. Plants such as penstemons, dahlias and delphiniums need to be regularly deadheaded, and you will be rewarded with new blooms for many weeks to come.
2 Plant new perennials, as the soil is still warm and moist enough for the roots to get established before winter. Give new plants a good soak before planting and mulch around them when planted to keep moisture in the soil.
3 Divide clumps of perennials that are becoming old and bare in the centre. Use two forks if you can and prise through the clumps, pulling them apart gently. Trim off excess foliage and replant new, smaller clumps in soil that has been well prepared with organic matter. Groups of three or five look best – and make sure you water well.
Begin lifting root vegetables
Turnips, carrots and beetroot can all be lifted and stored over the winter. You can leave parsnips in the ground, though, as some people say they taste better when a bit of frost has got to them.
If you are storing root vegetables, look for those that are undamaged, as they may spread disease otherwise. To store, place the vegetables in a box in a frost-free place, layer them in sand, which prevents them from drying out too much, and keep them dark, which discourages any growth. Keep checking to make sure none are rotting and you will have homegrown vegetables for many months to come.
Be inspired by a tiny urban garden that provides enough fruit and veg for the family all year round
Turnips, carrots and beetroot can all be lifted and stored over the winter. You can leave parsnips in the ground, though, as some people say they taste better when a bit of frost has got to them.
If you are storing root vegetables, look for those that are undamaged, as they may spread disease otherwise. To store, place the vegetables in a box in a frost-free place, layer them in sand, which prevents them from drying out too much, and keep them dark, which discourages any growth. Keep checking to make sure none are rotting and you will have homegrown vegetables for many months to come.
Be inspired by a tiny urban garden that provides enough fruit and veg for the family all year round
Start pruning climbing roses
Your climbing roses are ready to be pruned when you see the flowers have started to fade – if they’re not there yet, you can wait till next month.
Remove any diseased or dead wood, cutting at an angle, which you should always do when pruning to prevent water getting into the cut area, and then tie in any shoots that are left and are coming from the base. If you have a rose that’s not showing any basal stems coming up, then you should prune all the existing side shoots back to about two or three buds or leaves.
Your climbing roses are ready to be pruned when you see the flowers have started to fade – if they’re not there yet, you can wait till next month.
Remove any diseased or dead wood, cutting at an angle, which you should always do when pruning to prevent water getting into the cut area, and then tie in any shoots that are left and are coming from the base. If you have a rose that’s not showing any basal stems coming up, then you should prune all the existing side shoots back to about two or three buds or leaves.
Thin out congested pond plants
You may find that many plants have taken over your pond, covering most of the water. When you remove a plant, leave it on the side of the pond for a day or so for any wildlife to crawl back in.
Then, as with any other perennial, you can chop the plants in half or divide them, making sure each piece has a good root system. Repot with aquatic soil covered in a layer of shingle. Don’t worry if the plants have lots of roots coming out at the bottom of their baskets – you can quite happily slice them off and the plants will be fine.
If you have a pond near trees and usually net it come the autumn, you can start to do this towards the end of the month, especially if you have fish, as rotting leaves produce toxic gases, which can be lethal to wildlife as they decompose.
You may find that many plants have taken over your pond, covering most of the water. When you remove a plant, leave it on the side of the pond for a day or so for any wildlife to crawl back in.
Then, as with any other perennial, you can chop the plants in half or divide them, making sure each piece has a good root system. Repot with aquatic soil covered in a layer of shingle. Don’t worry if the plants have lots of roots coming out at the bottom of their baskets – you can quite happily slice them off and the plants will be fine.
If you have a pond near trees and usually net it come the autumn, you can start to do this towards the end of the month, especially if you have fish, as rotting leaves produce toxic gases, which can be lethal to wildlife as they decompose.
Go for grass
Grasses really come into their own from September onwards and fill the gap in many borders. They work really well with many perennials, such as echinacea, perovskia, anemone, rudbeckia, and helianthus, for example.
Don’t be tempted to cut grasses down, even if they look a bit sad or windswept, as they will continue to hold the border together right through the autumn and into winter, prolonging interest, and some look wonderful in the frosts. There are lots to choose from and they look good either in groups or spread out among perennials.
Grasses really come into their own from September onwards and fill the gap in many borders. They work really well with many perennials, such as echinacea, perovskia, anemone, rudbeckia, and helianthus, for example.
Don’t be tempted to cut grasses down, even if they look a bit sad or windswept, as they will continue to hold the border together right through the autumn and into winter, prolonging interest, and some look wonderful in the frosts. There are lots to choose from and they look good either in groups or spread out among perennials.
DIY your own composter
Make a compost bin for all your autumn debris. It’s so easy to make your own garden compost and, with autumn on the way, fallen leaves and cut soft stems will rot down, providing a rich garden medium to return to the soil.
You can easily build a compost bin – and it doesn’t have to involve as much carpentry as the one pictured here. Simply set four sturdy upright posts into the ground in a square, about 2.5ft apart. Attach chicken wire to three sides, leaving the front open.
Add cardboard to the insides and gradually layer garden refuse (no woody stuff), grass clippings and kitchen waste, mix it in well and cover with a bit of old carpet. Turn regularly and in no time you’ll have lovely home-made garden compost. No need to lug huge bags back from the garden centre any more!
TELL US…
What will you be doing in your garden this month? Let us know or share your photos in the Comments below.
Make a compost bin for all your autumn debris. It’s so easy to make your own garden compost and, with autumn on the way, fallen leaves and cut soft stems will rot down, providing a rich garden medium to return to the soil.
You can easily build a compost bin – and it doesn’t have to involve as much carpentry as the one pictured here. Simply set four sturdy upright posts into the ground in a square, about 2.5ft apart. Attach chicken wire to three sides, leaving the front open.
Add cardboard to the insides and gradually layer garden refuse (no woody stuff), grass clippings and kitchen waste, mix it in well and cover with a bit of old carpet. Turn regularly and in no time you’ll have lovely home-made garden compost. No need to lug huge bags back from the garden centre any more!
TELL US…
What will you be doing in your garden this month? Let us know or share your photos in the Comments below.
If you have an unheated greenhouse, you can still grow some lovely plants, especially alpines that hate being wet but don’t mind the cold. In fact, if you keep the greenhouse well ventilated over the winter, many plants, even some shrubs, will benefit from being under cover.
Hardy cyclamen will brighten up the dullest of days under glass and winter-flowering shrubs, such as Viburnum x Bodnantense ‘Dawn’, which smells wonderful, does well under glass for the first year. If you visit garden centres, you’ll see a great many plants doing very well in cold glasshouses over the winter, so take note of what else you could grow.