While collecting a bag of Organo-Fert from Unley Council last week I noticed that they are selling discounted worm farms of several types too, as well as the worms too! That really is closed loop recycling. Incidentally I’ll swear that my silverbeet turned a greener shade of green in just four days after getting their Organo-Fert top-dressing.

A Clapham reader wrote asking why her container grown ‘Meyer’ lemon had dropped all its fruit recently and she’d noticed white flies all over it, so where they the reason? Well probably not directly. White flies do sap the nutrients from plants they feed on but it’s more likely that your potted lemon needs feeding much more often than the once a year you admitted to. The nutrients leach rapidly and I’d suggest any citrus in a pot get fed at least monthly from August through summer to April.

There’s a lot of interest in White flies at present and questions ranging from “are they safe to eat since I’ve swallowed a few inadvertently while gardening”. Quite safe fortunately. Another question was “what is their life cycle since there appears to be nothing on the Internet about that?” The females are laying up to 200 eggs each at present that over winter on falling dried leaves to emerge in spring. I have gained control by a spray of PestOil on the affected plants and composting or disposing of all leaf litter with eggs on them.

A local sandwich bar in Halifax Street Adelaide, was so troubled by white flies affecting outside customers that he erected sticky traps and sprayed the near by Ash trees as a precaution. Business has improved markedly!

The mild weather we’ve been having always leads to an insect population explosion at this time of year and weevils eating leaves is pretty common right now on a wide range of plants. So what to do? Well there is the torch in the garden in the dark. One weevil does a lot of damage and they move really slowly at night. The other approach is to spray a cordon around affected plants of Carbaryl. Not onto edible plants although the label says you can do that on certain crops and observe the recommended withholding period before harvesting. Carbaryl attracts eating pests, such as weevils, millipedes and caterpillars, so use it as a spray around your garden rather than on the plants.

I had an enquiry recently about “how to control soil nematodes?” Gardeners often tell each other that all you need to do is plant perennial marigolds, that’s Tagetes lemmonii or T. lucida, but what is not relayed is that these plants take years to build up enough of the allelopathic substances in the soil to provide a barrier and on some soils, not at all. The ornamental bedding marigolds, be they French, African or American will not in their annual life cycle provide any benefit at all! So what to do?

Primary Producers have for a few years now been getting good control by resorting to bio-fumigation amongst their vines and citrus orchards, by planting several Brassica species known to have excellent allelopathic activity in the soil. The brassicas in this mix grow to about 20cm high and leach substances as they grow that inhibit weeds and the passage of soil nematodes and root knot nematodes, which eat your plant roots.