Sweet smell of cooking success
Harvest yams
The flavour of yams is better after a few frosts so wait until cold knocks down the leafy tops of the plants before harvesting. It’s a good idea to put in a stake next to each plant, so you don’t miss any come harvest time.
When harvesting, use a spade to lift and dump all the soil on to a tarpaulin. Then sift the soil thoroughly to make sure you don’t leave too many tiny tubers in the ground, as these will sprout the following year but are unlikely to amount to much more than a nuisance.
You can grow your own yams from storebought or home-saved tubers, or buy seed tubers of special varieties from garden centres. They come in a range of colours from gold to orange and traditional red.
To store yams for replanting in spring, keep them in a paper bag in a cupboard indoors.
Plant yams in fertile soil in a sunny position. Space them 30-40cm apart, burying the tubers 5cm deep, and mound up. Dig in compost prior to planting and side dress with fertiliser when the tops emerge.
Prune wisteria
Whether trailing across a villa veranda or dangling from an archway, wisteria in full bloom is spectacular, but they are not plants you can love and leave alone. They need pruning twice a year, or they will swamp whatever they are growing on even ripping apart weather boards and wrenching off guttering.
Last summer organised gardeners will have shortened all the side shoots to about a forearm’s length to encourage formation of flower buds. Now the leaves have dropped it’s time to shorten those side shoots again to about a finger length or just a couple of buds.
While you’re there, remove any unwanted, diseased or damaged material and shorten any side canes to around 10-15cm or about four fat buds. This will encourage more flowering spurs.
Acid or alkaline?
If you are planning a new vege patch or flower bed for spring, it’s worth taking the time to find out your soil pH. The pH scale measures soil acidity from 1.0 to 14.0. Water is neutral at 7.0. Anything below that is acidic, anything above is alkaline.
Most veges prefer a slightly acidic soil – a pH level between 6.5 and 7.0, although some plants are fussier than others. Brassicas like alkaline soil, whereas potatoes and citrus trees prefer acidic soil.
Acidic soils can be treated with lime in autumn and early winter so it has time to dissolve completely before the main growing season begins in spring.
Alkaline soils are trickier to treat, but mulching with pine needles can slowly lower pH.
To test your soil pH – and find out its nutrient levels – order soil testing kits from Hill Laboratories or buy cheaper DIY kits from garden centres.