Landscape gardener and Life columnist Justin answers your question.
I am a first-time gardener. I have planted some herbs, but the basil leaves have holes in them despite my spraying a commercially prepared insecticide.
- Mohini
It could be caterpillars but small slugs are more likely. Caterpillars can leave little tell-tale green droppings. Check at night to see if you can catch the slugs at it. Try planting the basil in pots away from your main garden for a while; cover the ground where the eaten basil was with cardboard. Any small slugs will start living under there and will be easy pickings during the day. Once the ground is clear of slugs then go for gold. Keep going and good luck.
Your item regarding passionfruit reminded me of some problems I have with this plant. My two vines crop quite well, but when the fruit is large and green some of them start to wither and then drop off. Is this a reaction to overcropping?
The other problem is that when the remaining fruit is just beginning to turn purple, many of the leaves turn yellow and fall off.
Our soil is very sandy but I have a sprinkler system operating. I put a citrus fertiliser on 2-3 times a year. Occasionally I spray them when spraying the nearby tomatoes.
- Frank Coulter, Pauanui Beach
I think both problems are related to water retention. While passionfruit don't like to have wet feet they will stress under very dry conditions, especially when in full fruit. You say you water a lot but I would try hose watering instead of a sprinkler, and I also recommend mulching. In your case you may want to consider forking compost into the root system around the plant to help with water and nutrient retention. Other problems with the leaves are spread by passionfruit vine hopper. This is more of a problem if the plants are dehydrated, but a precautionary spray once every two weeks with soap and oil should help.
I've planted comfrey around the bottom of my fruit trees (plum, apple, peach) as the start of a herbal ley. It is well contained by retaining walls, so won't be spreading, but I was wondering whether that is enough to keep the trees fed? Should I be planting other herbs too?
- Isabel B, Birkenhead
Once the comfrey takes hold other herbs will find it difficult to establish. Birkenhead has a heavy clay soil so composting and mulching are very important for you and you can do this when the comfrey dies back. You can still fork sheep pellets and blood and bone around the tree as the comfrey is tough enough to take a good natured lacerating.
Weekend checklist
* Collect seed from corn, beans, tomatoes and anything else you want to grow next year.
* Mulch after it rains. Makes best use of the wet weather.
* Keep up with courgette and cucumber harvest. These plants will start showing serious signs of deterioration. You can spray for fungus and mould using copper-ox-chloride or baking soda spray, but I usually don't worry about it as the plants have almost reached their use-by date.
* Sow late season peas, basil, lettuce and coriander.
* Plant leeks, celery, cabbage, cauliflower, silver beet, carrots, beetroot, parsnips, late potatoes.
* Keep gardens clean and tidy but leave a few plants to go to seed. These weaker plants attract pests and diseases
* Collect seed from herbs, tomatoes and anything else you want to grow next year.
* Get garden beds ready for winter by composting or building up your garden layers no-dig garden style, or by green cropping.
* Keep planting marigolds, petunias and other annuals.
* Deadhead flowering evergreens such as day lilies.
* Chop back scrappy foliage and diseased wood.
* Start pruning roses a little harder and spray for mould and fungus.
* Lightly trim hedges, and I mean lightly - any holes in your hedge now may not fill out until spring.
* Mix hedge clippings into your compost and turn well.
* Get your teaspoons ready for feijoa season.