September has a tendency to slide in like the bill under a hotel room door, quickly and quietly without you noticing. But once you do, then the tell-tale signs signifying the end of summer are there. Our list of September bonsai jobs are all about looking ahead to the autumn, and preparing our garden and trees for what is to come. 

September is the start of the meteorological autumn. Whether we like to admit it or not, the nights are visibly drawing in and there is the increasingly frequent morning dew on the grass.

It reminds us to take the time to enjoy the remaining sunny days that we may get, sit out with a favoured drink and be thankful for what sunny rays we can still find.

But for those times when you do not have a cuppa in hand, here are our list of bonsai related jobs for September.

Reduce feeding

Bonsai trees will be looking forward to their long needed rest and recuperation after the spring and summer exploits. In order to help in this process, reduce feeding or switch to a low nitrogen feed. This will prevent the tree from attempting to put on new growth.

Frost protection

If you have any trees which are not fully hardy, then start making preparations to move them under shelter. This may be a cold greenhouse, veranda or conservatory. Identify the trees that you need to protect and where you are going to locate them, then keep an eye on the weather forecast.

Clean out cold frames and greenhouses

Whether out of necessity or cautiousness, many of us put trees under glass (or plastic) over winter. September is a good month to clean out cold frames and greenhouses in readiness for use over the colder months. It not only improves light levels but also helps to reduce levels of pests and decease.

Use a detergent to clean both inside and outside glass surfaces and also structural parts. Remove any weeds which have been taking up residence and also undertake any repairs needed.

Check your trees

With the root growth over the previous months, trees will have pushed out more roots within the pot. This may lead to congestion and reduced drainage through the pot as a result. With the wetter months approaching, make sure that the water is able to drain through the pot and away to prevent water logging. If necessary, push a chopstick or screwdriver through the soil to add drainage.

On the subject of water, check your trees to see if they need watering before reaching for the watering can. Your trees will not need to be watered as often now that the height of summer is over.

Regularly check your wired trees to ensure that the wire is not likely to start cutting into the tree. Many trees can thicken at this time of year and in particular pine trees. A branch with wire marks can take years to grow out so vigilance is key.

Net ponds

If you have a garden pond, and many bonsai enthusiasts do, now is the time to place netting over it. This will prevent falling leaves from entering and decomposing in the water. Decomposing leaves will add unwanted nutrients to the water which increases algae and pond weeds in warmer months.

Thinking ahead

If you are planning to wire any of your trees in autumn then you may need to purchase wire or other sundries in readiness. Wire diameter should be approximately a third to half the diameter of the branch or trunk that you wish to bend.

Hit the Garden Centres

September is a good month for buying reduced plants and trees from garden centres. End of season sale signs go up and the clearance sections fills with unsold and damaged stock. As bonsai people, we often look for the oddly shaped tree and now is the perfect time to add to your collection.

Enjoy the weather while you can and best of luck in those sales.