September

Greater Brisbane region

It's springtime! There's lots to see and lots to do this month, so set the alarm clock early.

Even if you're not doing any major pruning, the end of flowering is a good time to fertilise because the majority of garden plants will be putting on new growth in the coming months. Water is the other big necessity, and goes hand in hand with fertilising. Keep water up to actively growing plants, especially after hard pruning, or if they are flowering or setting fruit. If it's dry and you can't water, it may be advisable to hold back on pruning and fertilising. More about watering in the August entry.

Fertiliser sold as "general purpose" will serve most well, but be careful with grevilleas, banksias and others in the protea family. A low-phosphorus native plant fertiliser will be better for those. Specialised azalea and camellia fertilisers are available for these and other lovers of acid soils. Other types of specialised fertilisers are fine-tuned to suit particular purposes. If in doubt, ask at your local garden centre.

Besides supporting a quantity of new foliage development, good nutrition is important for quality. Healthy plants will be better able to naturally resist or tolerate pests and diseases. If you're considering additional controls for problems like azalea lace bug or the many citrus pests, don't forget that the best time for treatment is before the damage is obvious.

Prune winter/spring flowering shrubs as they finish (see also notes for October. Don't forget the natives such as callistemons, grevilleas. This not only encourages an attractively shaped dense bush with more flowers next time (and low, where you can see them), but prevents the plant wasting energy on the production on fruit and seeds.

Some poinsettias (Euphorbia pulcherrima) may still be showing some colour, so leave those until October if you prefer. However their relative the Snowflake (Euphorbia leucocephala) should be well and truly finished by now, so cut back (if you haven't already) to control size and shape.

Pruning of azaleas isn't essential, but if you like a clipped look, or feel that they're getting too big or too straggly, immediately after flowering is the time for any major pruning. New growth can be trimmed again before Christmas to encourage bushiness and more flowers next spring (This may result in loss of flowers if you have one of the newer repeat-blooming types like the Encore series). If you just want to take out the odd long branch to tidy the shrub while retaining a naturalistic look, cut back well into the middle of the shrub. Fertilise, mulch and ensure adequate water supply in the coming months.

Many summer-autumn flowering shrubs produce their flowers on new growth, and pruning can stimulate lots of new vigourous shoots that look dense and bushy and will carry lots of flowers, while maintaining the plant at an appropriate size.

September is considered by many local growers as the best month for Hibiscus pruning in SEQld. Although August may be actually be better (see August entry for more information), if you haven't cut back already, prune asap as they will be wanting to put on new growth..

Also cut back other summer-flowering tropical shrubs like allamanda, pentas, plumbago. This is also a good time to attend to tropical foliage like acalyphas andcrotons, or non-flowering hedges prior to the restart of growth that comes with warmer temperatures. If you live in a cool district, you may prefer to delay until late in the month or even next month to ensure fast and healthy regrowth.

Trim Argyranthemum, commonly known as marguerite daisy , when flowering has finished (pictured left). Try taking some cuttings from the prunings to have replacements ready when the parent plants get past their best. More on these plants on the Daisies page.

Cordylines looking leggy? Cutback to encourage branching lower down. Don't waste the prunings - use them to strike new plants.

Fertilise and mulch the garden generally as growth steps ups with the warm weather. This is particularly important if you're trying to encourage a thick dense hedge and you're regularly removing nutrients in the form of clippings. Be sure to use a low-phosphorus formualtion for sensitive natives such as grevilleas and banksias.

Already the days can be very warm and sufficient water will also be required to support new tender new spring growth. If it's dry, provide supplemental water if possible, at least to your most valuable specimens.

If you have spring-flowering annuals, keep up the water and supplement nutrition with a soluble fertiliser to keep them producing as long as possible. Also remove spent flowers to encourage the formation of new ones. (see also Annual Flowers and other Bedding Plants.)

The Vegetable Garden

September is a peak planting month in SEQld if you want to capitalise on the relatively mild conditions of spring and early summer to produce a wide variety of vegetable crops. Things will become more difficult in the punishing conditions of mid summer.

If you still have space, you can also begin sowings of heat lovers like rosella, okra, snakebeans and sweetcorn.

It's tempting to get carried away when confronted with the variety of seeds and seedlings available in the garden centres, much less the many unusual varieties in the catalogues of specialist suppliers. Most vegetables need a constant supply of moisture to do well so do bear in mind your ability to keep the water up to plantings over the coming months.

With the weather warming up, pests become active and begin proliferating. Pests and diseases in general will be proliferating. keeping on the front foot both with respect to prevention and control measures, as well as attending to the health and vigour of the plants themselves so that they can resist and outgrow attacks, will help protect the investment of time and energy you've already made in establishing crops.

Try to minimise population buildups by being vigilant now. however, newly hatched pests or isolated attacks can be difficult to spot, so be proactive. For example, protect young tomatoes and other susceptible fruit from fruit fly with with appropriate bags or nets and set up fruit fly traps. Cabbage White butterflies may look pretty fluttering over the vegetable garden, but if they get the chance their caterpillars will quickly demolish cabbages and related crops. If you still want to plant them, be prepared to take precautions.

Fruit Trees

Sorry, I haven't prepared any monthly notes for fruit trees yet.

The Flower Garden

See also: Annual Flowers and Bedding Plants, Seed raising

Garden shows, open gardens

At this time of the year many garden shows, garden festivals and garden openings are held. There will sure to be at least one you'd like to attend. Besides being a great source of information and ideas, hard-to-find plants and other items for the garden are often available for sale at such events. Check the Gardening Events Diary to see what's on in your neck of the woods.

Looking ahead

While September is a big month for garden shows and open gardens, there are plenty of places to go October, too. Visit the Events Diary and see what's on. Also, don't forget that Christmas is approaching, so keep an eye on those market stalls for garden-related gifts. If you need some more ideas, visit Garden Gift Ideas.

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