Our District

March in the Garden

It’s been a strange summer – but whatever your harvests have been, this is the time of year when gardens start to look a bit seedy. A big clean up can help morale: recycle gone-to-seed lettuces and dried out calendula on the compost pile.

As always in the garden, the best direction to look is ahead to the coming season. Take stock of your garden, noting anything you want to change or move once autumn rolls round.

Winter veges like broccoli, cauliflower and leeks need to be in the ground within the month to build up size before growth slows down in winter. Compost needs to be made for next spring’s plantings, and fruit trees need pruning and shaping, after harvest, for next year’s crops.

 Late Summer Jobs:

  • Plan your winter garden, preparing beds for garlic/ leeks/ winter greens/ brassicas/ carrots/ beetroot/ green manure crops. Dig in any green crops (eg areas of borage or calendula) and add manure and compost for brassicas or leeks, but not for root crops. If growing from seed, sow them now to be ready for planting out in about 3 weeks.
  • Pest patrol: Pests are out in full force in the warm, dry conditions. Use digital control (finger and thumb) to squash green shield bugs and looper caterpillars. Look them up to learn about their life cycles and how to best manage them without poisonous sprays. Spray brassicas with organic Bt spray, or cover with nets, to stop white butterfly damage.
  • Once pumpkins have set some fruit, or outgrown their space, you can pinch out the vine tips (these are also edible.) Don’t worry too much about a bit of mildew on the leaves- it generally means the plants are drying out at the roots, so give them some water, cut off the worst leaves and spray with milk/baking soda if you feel like it.
  • Watch for blight. Cut affected lower leaves from tomatoes and burn or bin them. Avoid watering onto leaves - water the soil instead.
  • Add liquid feed like seaweed concentrate to your watering can, especially for plants that are fruiting. Keep watering to shallow-rooted feijoas and citrus to fatten their fruits.


Plant: Brassicas, lettuce and other salad greens, red onions, leeks.

Sow: Carrots, beetroot, coriander, rocket, calendula, peas (direct); alyssum, lettuce, late leeks, peas. Kale, broccoli, cabbage, cauliflower (in trays, protected from white butterflies.)



This month we look at brassicas: Kale, cabbage, cauliflower, broccoli, mustard greens.

  • These do best with lots of good compost and seaweed. Add plenty of nitrogen (eg manure) for leafy cabbages and kale, with extra potassium (eg wood ash) for `headers’ like caulis and broccoli.
  • Plant a variety, for different harvesting times – you may not be picking sprouting broccoli until spring, but you’ll be glad of it then. Purple frilled kale, or purple caulifowers, add some colour to the bed. If you’re not growing from seed, the newspaper parcels at the supermarket are good value, but plant the next day if possible.
  • Sometimes it’s hard to find space for the winter crops when summer ones are still growing, but getting in brassicas early (March at the latest) is crucial if you want to be eating them before spring. Make new beds if needs be.
  • Plant seedlings lower than they were in the punnets, firming them in `up to their necks’ (ie right up to the lowest set of `leaves’ - actually the seed leaves or cotyledons.) This reduces wind rock, a common reason for crop failure - it’s hard to grow big when you’re being shaken back and forth by every gust. Compost can also be piled up around brassica stems as they grow.
  • Water in each seedling with a cup of liquid feed (seaweed or manure tea). Keep watered in dry spells.
  • Protect from cabbage white butterflies and their green caterpillars using netting or a bT spray. bT is an organic bacterial spray that interferes with caterpillars appetites, starving them to death without affecting other insects. Derris Dust, formerly organically approved, has now been linked to nerve damage and Parkinson’s disease.
  • Mustard is a great, easy cover crop over winter. It can be broadcast-sown (sown directly onto beds) in autumn; young leaves are picked for salads (delicious with something sweet, like grapes, and a squeeze of lime juice); older leaves can be cooked in stir-fries or boil ups and any leftover leaves and stems can be dug in as green manure or put on the compost heap. Mustard is rich in sulphur, a natural steriliser, so it’s good to grow where you have had disease problems.


The Council Green Gardener, Hannah Zwartz, offers sustainable and waterwise gardening advice to local residents, community groups and schools.

Community Visits and workshops are free. Get together five friends or neighbours and invite the Green Gardener round.

Contact Hannah through the Council Service Desk 296 4700 or at greengardener@kapiticoast.govt.nz

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