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Tips for spring gardening

As the new season’s growth takes off, gardeners have plenty of jobs demanding attention. However, not all are best done now.

Now is a good time to add organic goodies to your vegetable garden. Photo/Thinkstock

With winters becoming milder, spring is turning into a greater conundrum for me. I’m all set to start gardening again, but my garden hasn’t stopped growing.

One lonely capsicum remains on last summer’s plant, which I hope might carry on for another season; the broad beans are a mass of blooms; I have sweet peas filling a wine barrel; and my raised beds are full of greens. The only option is expansion, but the most promising spot is occupied by a large composting pile at the end of the garden path. However, a move must be made or we won’t have room for a summer harvest.

Spring certainly puts enthusiasm into a gardener’s step, and although there are plenty of jobs to be done, some are best left until other times of the year.



Let weeds seed today and your trouble will more than double. Once you’ve gone to the effort of weeding, make sure you cover the exposed soil with a good layer of mulch. If you want to use straw, remember to use pea straw rather than farm straw, which is usually full of grass seeds.


Much like potatoes, kumara need to be sprouted before they can be planted out. To ensure they’re ready for planting out in October, get them under way now. Old council recycling bins are great for this process, or use a 20cm-deep plastic tray. Start the bed with a 10cm layer of freshly decaying horse manure, then add a centimetre of straw and top with a 3cm layer of sand into which the tubers should be gently pushed. Cover the bin or tray with a glass sheet, but ensure you lift it every day or so to let in fresh air. The manure creates heat, so within 4-8 weeks the kumara will have sprouted. Once this occurs, cut off each sprout ready for planting.


If you have a kitchen garden, think of ways to attract more pollinators. Adding flowering plants, such as borage, lavender and cleome, or natives, such as manuka and flax, will encourage bees. If you’re planning to use insecticides, first think about the potential effects on your health as well as on the beneficial insects that add to a garden’s productivity and general health.


An easy-care crop with great rewards, asparagus needs long-term commitment because, unlike other crops that can be rotated at different times of the year, the plants stay in the ground from one year to the next. Plant asparagus any time from now until December. This vegetable needs a sunny aspect and free-draining soil with layers of well-prepared compost. If you plant now, next spring you’ll be congratulating yourself on your far-sightedness as you look forward to the first harvest.


Although spring weather is unpredictable, it’s easy to get seeds safely under way. Most gardeners still expect cold snaps for the next month or so, but young plants can be protected if you start them off in a small plastic greenhouse or miniature glasshouse made from an old window laid over a simple wooden box. (This is a DIY version of a cold frame.) The window can be lifted or “opened” during the day to provide ventilation, then lowered at night to protect plants against frost. Small ready-made tunnel houses are also available and can be popped over young seedlings to protect them as they grow, but remember to lift off the covering on sunny days to help the plants harden off.


Outside: carrots, parsnips, cabbages, salad greens, onions, leeks, beans, broad beans, peas (south of Auckland), snow peas, corn, amaranth, beetroot, radishes, celery, coriander and basil.
Under glass: chillies, cucumbers and aubergines.


A winter garden doesn’t need fertiliser, but now is the time to start a feeding programme again, and any organic goodies will be welcome. Everything from trees and shrubs to small plants will thank you for some sheep pellets, blood and bone or just a good mulching with well-prepared compost. If you’re using fresh organic material such as seaweed or manure, it will need to rest and be dug through for a good month before the soil can be used for planting. Spring is also a great time to clean out worm farms. The castings can be dug into new vegetable beds and the juice applied to the garden. I use mine on everything from daphne, nikau and native ferns to food crops. It’s also a good time to dig in green crops, either straight after harvesting or after allowing them time to compost.



Don’t plant out tomatoes until after Labour Day. If you have a hothouse, they can be grown earlier, but otherwise it’s best to wait. Labour Day aligns with the traditional Maori planting calendar and is the best time to plant tomatoes.

Don’t prune camellias once new spring growth begins, usually around late September, or the following year’s flowering will be reduced. The pruning window is short: it must be done between the end of winter and in this first month of spring, essentially after flowering but before the first flush of new growth. If you want to prune heavily, the rules are the same, but expect a poor flowering season the following year as the plant re-establishes its foliage.

Don’t prune hydrangeas. As pruning now will prevent flowering, it’s best to leave it until late summer. Deadheading is fine once the hydrangeas have bloomed, and from late summer through to winter you can prune as you please. lNow is a good time to add organic goodies to your vegetable garden.

Send your questions to: goodtogrow@xwd.co.nz