Welcome to your one-stop resource for gardening in September. If you always feel like you don’t have enough time for gardening, or just need some guidance on what to focus on each month, this is the series for you!
You can check out my garden jobs for every other month in this post.
Gardening in September
The arrival of autumn slows things down in the garden; plants are starting to shut down, lots of crops are coming to an end, and leaves are starting to fall. This doesn’t mean there’s nothing to do this month though! There are plenty of jobs you can make a start on that will prepare your garden for the cold weather and the spring that follows it.
Here are some ideas for ideal jobs to tackle if you’re gardening in September.
Divide summer flowering perennials
It’s a good idea to divide perennial plants every two to three years, because doing so gives them a new lease of life. It’s also a great way to create new plants for free.
Summer flowering perennials such as crocosmia, geranium, hosta and euphorbia can be divided in autumn, just make sure they have finished flowering first. It’s a quick and easy job, my free plants post shows you how to do it.
Plant spring bulbs
We may be heading towards the colder months of the year, but planting spring bulbs is a gardening job that really gives you a lift. *Spring bulbs flower when most other plants are still waiting for warmer weather, so they make such a difference to the amount of interest in your garden at the end of winter.
Daffodils, crocus and hyacinths should all be planted by the end of September; hang on a bit longer to plant tulips though. If you’re not sure how to do it, check out my post on how to plant bulbs.
It’s also worth potting up a bulb lasagne; this is a container layered with bulbs that flower at different times, and it’s a brilliant way to get a long display of flowers for minimal effort. Another great idea is to pot up some of those bulbs and ‘force’ them to flower early, so you can enjoy the blooms indoors before spring arrives. My post on forcing bulbs takes you through this step-by-step.
Autumn lawn maintenance
After a dry summer and lots of footfall, your lawn is probably in need of some tlc. Use a *garden fork to make holes in the lawn at regular intervals, this aerates the ground and helps avoid waterlogging and compaction.
This is also a good time of year to rake any ‘thatch’ from the surface of your lawn. Thatch is dead grass that becomes matted at soil level, and it can really inhibit growth of new grass. Be warned: this job is a good workout!
Keep collecting seeds
By this point in the year, lots of plants will have finished flowering and will be developing seed heads. Saving seeds from your plants is a great way to get more plants for free, and it’s really not difficult.
Choose a dry day to harvest your seeds. Snip off the stem just below the seed head, and pop it into a paper bag or envelope where you can shake the seeds out and discard the rest of the seed head. Remember to label each bag!
Try not to harvest every single seed head. Leaving a few on the plant can provide structure and interest later in the year, while also being a food source for local wildlife. Leaving seed heads will also mean the plant can self-seed in the soil nearby.
Sow green manure
Green manures are plants that you grow to cover bare soil when you’re not using it. They’re a great idea for the less productive, colder months in the garden. The foliage keeps weeds down, and when you dig the plants back into the ground, they enrich the soil and improve its structure.
Good varieties of green manure to sow at this time of year are winter *grazing rye and *winter tares. Scatter the seed thinly over the soil, then rake over. When you want to use the land again in spring, cut the foliage down and leave it to wilt before digging everything back into the soil.
Take cuttings of tender perennials
If you’re worried about tender plants surviving winter, you can take cuttings of them now as an insurance policy. This is also a great way to increase your stock of plants.
Fuschia, salvia, verbena, pelargonium, penstemon and coleus are all good candidates for taking cuttings this month. The RHS has a great guide to taking cuttings here.
You will need to give your cuttings some protection over winter, so make sure you think about how much space you have before you get carried away!
Raise containers off the ground
Leaving containers on the ground makes them more likely to get waterlogged, and most plants hate sitting in cold water over the winter. Raise pots off the ground by using bricks or *pot feet, to help excess water drain away.
Now is a good time to prune any shrubs that flower in late summer, to keep them looking good. Tender shrubs such as fuschia can also be pruned this month if they’ve finished flowering. Use *secateurs to remove the oldest stems at the base, this will encourage new growth for next year’s flowers.
Climbing roses and rambling roses can also be pruned this month if they have finished flowering.
If you have any trained fruit trees, now is the time to cut back new shoots. Leave about five leaves on the new growth. Summer fruiting raspberries (as opposed to autumn fruiting varieties, which are still producing fruit) also need a bit of maintenance at this time of year. Remove all brown canes that bore fruit this year, cutting them down at ground level. There will be new, green canes that have grown this year, these are the ones that will bear fruit next year. Thin these out if you need to, and tie them into your plant supports.
What to plant in September
September is quite a productive month for sowing seeds, planting bulbs and growing new plants – some to enjoy soon, and some to get started for next year. For a full list, head over to my post on what to plant in September.
What jobs are you tackling in the garden this month?