Landscape gardener and Life columnist Justin answers your questions.
I have large avocado tree which is flowering profusely in spring but produces hardly any fruit. As it is now outgrowing its position I would like to trim it back. What time is recommended without harming the tree too much?
I had the same trouble with my tree. Firstly, I'm going to assume your tree is a grafted tree bought from a store. In my case, my avocado was still juvenile, which does make a difference, but friends of mine had fruit straight off the bat. I found watering during flowering and for a good time after, until the fruit is starting to develop, was helpful. The best thing I did though was mulch under the tree. I used seaweed to do this because it is supposed to help flower-set. Otherwise I just let it do its thing and this year we're enjoying a good crop. Trim your trees at the beginning of winter before the flowers set and remember to mulch. This will regulate water transference and keep the shallow roots warm.
You mentioned green walls in your previous column. Could you please suggest companies that specialise in constructing green walls, giving advice etc?
There are quite a few systems on the market but one I could recommend is the Woolly Pocket from Natural Tree Products. Woolly Pocket is easy to use and comparatively light on the wallet. Unlike some self-supporting systems, this one requires an existing wall. The main thing is to watch out for maintenance. You want to either go for quick turnover plants such as veges, and herbs like basil, colour with plants like pansies, or real stayers like succulents, agave and other drought tolerant plants. Make sure you adequately water your wall and plant plants which will enjoy the aspect you're growing them in.
Can you please recommend an evergreen climbing plant for a trellis 4 metres by 2 metres tall, facing east to west. I need to plant it on the south side of the trellis. I prefer a flowering style.
The biggest mistake I see with climbers is planting a sun-lover next to a shady wall or fence. The result is a wall of sticks with a few tufts of foliage and the odd flower poking out of the top. As far as shade-tolerant climbers go I'd recommend most clematis. Just make sure you have prepared the ground adequately and have a good free draining soil to plant it into. Also be realistic about the space around the plant. Another mistake I often see with climbers is trying to install them in an area that's too small. Clematis, like most climbers, have sensitive shallow roots which require plenty of room.
* Plant wild flowers now. Try to get them growing before it gets too cold, and the plants will then sit quietly through winter, ready to burst into flower in spring.
* Get your favourite bulbs in the ground.
* Harvest your feijoas. To get the best of them do this at least once a day. They freeze really well and make great chutney.
* Plant winter veges - it's urgent, urgent, urgent. If you haven't got yours in yet get down to Kings and grab some punnets as it's getting a bit late for seed (although it's still quite warm ... hmmm).
* Prune any trees which have finished fruiting. Dry out the wood and burn it so you can use the wood and burn it so you can use the ash on the garden, or chop it up fine and put it in the compost.
* Clean out your pond.
* Trim hedges.
* Mow your lawn short and thatch it with a leaf rake.
* Clean up foliage on garden beds; put mulch under trees.
* Dig up dahlias. All this late summer we weather will get them sprouting again and they'll lose condition before spring.
* Plant late summer herbs such as coriander and basil. Use heaps of seed as there is probably little time left for them to mature but these tasty little shoots are well worth the effort.
* Plant fast-growing greens such as mesclun and rocket every two weeks. These make great stopgap veges while the winter stuff comes on.
* Be sure to add lots of dry leaves to your compost to keep the fruit fly down. If it's a real problem use a bit of lime, but not too much. Lime regulates acidity and your compost enjoys a bit of acid.