What to do in the garden in September

29 Aug 2019

After the hive of garden activity during August , you might think that you can take it a little easy when managing your flora and fauna in September. But sadly, a gardener’s work is never done. As summer winds down and autumn starts gearing up, you’re heading into an entirely new season in which to consider what to do in the garden. While some outdoor heating will help you spend more time outside in comfort, the same can’t be said for your plantlife. September is the time to reap what you’ve sown earlier in the year, and start preparing for the colder months. Here’s what we recommend to get you started.

September Garden Jobs

Get Ready For Spring

Considering the less-than-hospitable conditions you’ll be facing towards the end of the year, no one could blame you for already thinking ahead to the springtime. It’s not blind optimism though—the best things to plant in September are the ones which reach their full glory during spring. Indeed, the sooner you prepare for the beginning of next year, the quicker the roots of those bulbs will bed in the soil, and the better they will grow. Bedding plants like hyacinths, daffodils and irises are all resilient to the colder winter months, but will only look their best during spring, provided they have been planted far enough in advance.

But preparing your garden for spring isn’t just about what you plant, but what also you pull up. Spending a substantial amount of September weeding your lawn and flower beds will get this unpopular job out of the way early and, since weeds tend not to grow in cold conditions, you’ll keep your garden looking and feeling its best for a good six months.

Start Your Compost Heap For The Year

Of course, all of those weeds—and anything else you’ll be trimming and pruning from your flower bed—need somewhere to go. Luckily, September is the perfect time to make a start on your annual home composting efforts. With months of brown leaves set to coat your lawn, now is the time to prepare your compost bin, letting you make the most of what your trees are shedding.

Although the act of composting doesn’t really gets started during the colder months, keeping as much of the right kitchen waste and leaf matter as possible in a large enclosed bin will help you to get the process underway without exposing this valuable waste to the elements. That way, when springtime rolls around, you’ll be able to give your newly-planted bulbs the nutrients they need quickly and cheaply, all because you planned ahead in September.

Clean Your Pond And Water Features

After spending the summer as your garden’s centrepiece, your pond or water feature is going to become just as much of a focal point for your September garden tasks. Unfortunately, this attention will primarily revolve around winding it down for the winter. As the weather gets colder, and the leaves begin to drop, there’s going to be a fair amount of regular cleanup work which will need to take place. Otherwise, these leaves will decompose into sludge, which will encourage the growth of algae and weeds, as well as getting caught in your pond’s filters and causing potential harm if you keep any fish. This is the point at which your pond's water pump will become your best friend.

September is also the best time to test your pond water quality, with the nitrogen cycle of ammonia, pH levels, nitrate, and nitrite being the four main components. Excessive levels of any of these are particularly dangerous to the fish, flora, and fauna living in your pond, so cycling the water with dechlorinators and beneficial bacteria is essential to keep it at its healthiest later in the year. Of course, if you don’t have fish, simply running a net through the water every few days should help get rid of any undesirable leaf matter.

Ripen Squashes And Fruits

If you’re growing any pumpkins or other types of squash, make sure you remove a few leaves to expose the fruits to the September sun. This helps them ripen quicker, ready to be harvested either this month or next. This same job should also be applied to any tomatoes, as cutting off the lower leaves and exposing the fruit will encourage them to fatten up and ripen, giving you a larger yield.

Sow Hardy Plants And Flowers To Grow Over Winter

Whether you’re growing in a greenhouse or using indoor trays, September is a great time to start sowing the hardy plants which can survive the lower temperatures. Getting the kids involved in growing hardy winter vegetables is also a fun activity for the end of the school holidays, and our big winter garden vegetable growing kit for kids is the perfect place to get them started.

Things like calendulas, violas, lupins, and hollyhocks should be sown in pots and kept in a cold frame, ready to be planted outdoors in the garden the following spring. Sowing helenium will help to attract bees and butterflies to pollinate your garden in the following year. Hardy geraniums, however, can be sown directly outdoors where you want them to sprout, along with Bishop's Weed, cornflowers, poppies, and poached egg plants. Sowing in autumn means these plants can grow strong, established roots over winter, which can lead to more robust flowers.

What Fruit And Vegetables Can I Plant During September?

Salad Greens

If you forgot to do it in August, leafy vegetables like spinach and pak choi can be sown in September. However, it’s important that you cover up any greens with a cloche or a fleece grow tunnel in order to keep the harsh weather away, but still let the sun and rainwater in. These can then be harvested over the following months, giving you an autumnal supply of fresh leaves.

Cranberries

Although they can be seeded anytime between September and November, we recommend planting cranberries in September, before it gets too chilly to work outside. Cranberries prefer acidic soil with bog-like conditions, so you may need to carefully prepare the area before planting them. This includes digging out an area and lining it with thick black plastic, before puncturing with a fork to allow for some drainage. Fill it with ericaceous compost and add a layer of horticultural sand on top before watering, making sure the soil is wet, but not sodden, as cranberries can’t handle dry conditions.

Peaches And Nectarines

The good thing about peaches and nectarines is that they’re hardy, and can tolerate a wide range of soils. However, the young fruits and blossoms are vulnerable to frost, so try and grow them against a south or west-facing wall to protect them from the cold. Alternatively, you could grow your peaches and nectarines in a fruit trug, which allows you to plant them any time between September and December, while bare-root plants should ideally be planted in November.

What To Harvest In September

There are a number of fruits and vegetables that will be ready for harvest in September, and you should definitely do so once they look ripe, to avoid any birds or other animals from snacking on them. You also need to make sure that crops aren’t left to over-ripen on the vine or tree, as this will make them mushy and ruin the flavour. Keep a close eye on what you’re growing so that you know when they’re ready for picking. Fruits and vegetables that should be harvested in September include: