I live on the central plateau at Turangi so we are a bit colder, more exposed and have a shorter growing season. We do have a greenhouse, however. Do you have a list of frost-free vegetables as I feel I could grow a lot more, but don't want to waste time making too many mistakes.

- Andrea Traub

There are many plants you can grow and grow better than we can in warmer climates. It's good to know you have a greenhouse which is really important for extending your seasons. A poly tunnel is something else I would recommend. The way you landscape your property can influence things so look for opportunities to create micro-climates. Walled gardens often work best in your situation. Crops I reckon would do well are many of the berries, including raspberries and blueberries, and don't forget stone and pip fruit like apricots, peaches and nectarines, apples and pears. Quinces will also be worth a try. You will be able to grow asparagus and sweet brussels sprouts. Bulbs like tulips and flowers like poppies should also flourish.

I'm using my summer break to plan what to do with my "blank canvas" of a back yard. It's north-facing, has clay soil (unfortunately), and I have two young kids who like playing soccer and cricket, so I thought I'd leave lawn in the middle and plant around the edges, but can't get too precious with delicate plants. I need big, hardy space-fillers, preferably ones that provide some colour through the year. Any suggestions would be appreciated.

- Connie

Sunny and north-facing sounds great but clay is always a problem for the gardener. Plants to surround your football pitch/lawn include many natives such as pseudopanax. These evergreens come in many shapes or forms and as well as being very hardy in clay conditions will do the space-filling job nicely. Lomandra longifolia is an Aussie native. A lush looking grass, lomandra really holds its colour, as does the doryanthes excelsa. Also from Australia, doryanthes has huge sword-like leaves reaching heights of 2.4m with a ruby red proboscis every other year. Don't forget mondo grass, a great ground cover in clay, as are many flaxes. My current pet flax is phormium tenax "peppie" which is a very small, upright plant with an excellent hardy quality. For some hardy colour try knophia in all its variations, day lilies and small manuka. Last but not least, the landscaper's best friend,
dieties grandiflora. Hardy, upright and pretty.

After reading your article on dahlias I planted some for the first time this year and they're doing beautifully. I'd like to "expand their range" next year. Do they "self seed" and spread naturally, or do I have to plant more next spring, or split each tuber and replant?

- Jane

Your best bet is to split the bulbs up when they are dormant during winter, but you can get some new and exciting variations by propagating from seed. Whatever you do I recommend you pull up your tubers. Split them by following the advice in the article you mentioned and save them for next season's garden. They are excellent for giving away or swapping.

Checklist

* Water and mulch everything.

* Dead-head flowers and make sure you keep your garden tidy so as not to introduce pathogens.

* Water your grapes, and organise some bird netting from Kings now.

* Keep cucurbits (melons, cucumbers and pumpkins) well watered and spray for fungus and mould with baking soda and seaweed spray - although try not to water the leaves. For a chemical solution visit Kings. As the season goes on it's quite natural for the leaves to deteriorate.

* Allow some plants to go to seed. This is a good idea especially around crops with stink beetle infestations. The seeding plants are weaker and more inviting to predators - they will prefer these to your stronger more desirable plants, plus you get the seeds.

* Start preparing the ground for late summer crops and long-maturing winter crops like celery and parsnip.

* Start saving seeds for next year. Some plants have handy habits which make storage easy, like sunflowers, but for others with less convenient habits, place a paper bag over the flower head and shake. Save the dry seed in envelopes and store them in a cool dry place.

* Keep seeding basil, coriander, lettuce and rocket. Propagate in the shade and water often, then plant out, again in the shade, to get a late harvest.

* Keep kumara off the ground. Grow the runners up tepees like beans. This will stop small tubers forming and give you a good harvest of tubby tubers.

* Summer is the perfect time to make compost. Keep it moist and turn it every time you mow the lawn. This will ensure lots of air and water keep the heap hot and with the summer sun blasting away, your heap will be positively atomic.