What to do in the garden this week

Get busy in the greenhouse

Plant the summer-heat loving crops now – tomatoes, eggplants, chillies, capsicums and cucumbers undercover. If you can get them, large grafted plants are well worth the money as they start producing earlier. Sow basil seed or transplant basil seedlings indoors, it’s still a bit soon to plant outdoors except in the warmest areas.

There might be frequent spring showers out of doors but remember that all plants grown undercover are dependent on the gardener for all irrigation. New seedlings and newly sown seeds are especially vulnerable to drying out. Water with a fine spray from a misting bottle or the fine rose of a watering can – and warm the water first, so seedlings don’t get a chilly shock.

Be generous with fertilisers but don’t overdo it. Regular dilute liquid feeds are better than a highly concentrated dose all at once.

Remember the pollinators. Attract them into the greenhouse by planting the nectar-laden plants they love in or near your undercover growing area. Be prepared to get busy with a paintbrush if your area lacks bees. Or for tomatoes, brush past or stroke the plants to dislodge and spread the pollen.

Sort out sun protection – for you and your plants! Slather on the sunscreen and wear a hat, even this early in the season the sun can burn. Shade the most delicate seedlings in your glasshouse too. Whatever system you use, it needs to be well-anchored so it doesn’t fall onto the plants and reversible so it can be taken away in winter. If you use paint to whiten a tunnelhouse panel or glasshouse pane for shade make sure it is water-based, so it can be washed off. A shaded spot is no advantage in the winter.

READ MORE:
* Heavenly hydrangeas: why New Zealand has the best garden plants in the world
* The elusive biodegradable pot: why it’s so hard for gardeners to be eco-friendly
* Sweetcorn growing guide
* When to sow seeds, when to plant seedlings

If you don’t have a greenhouse, get creative

Now’s a great time for sowing undercover. Don’t fret if you don’t have a glass or tunnelhouse. Lean a spare window frame against the side of the house. Or pull a plastic bag over four sticks to make an effective plastic house for the time it takes to sprout and raise your seedlings to the point where they can go it alone. Or an upturned jar or clear plastic packaging can provide the conditions needed for successful seedling production. When it comes to alternative glasshouses, you’re only limited by your imagination.

In my garden, the clear plastic cover over the raised bed I wrote about a few weeks ago became too hot, so I’ve replaced it with insect mesh. It allows the rain through and provides protection from the wind. The temperature is slightly warmer under the cover than outside, but there’s enough air movement to keep the plants from cooking.

Out with the old and in with the new

The best celery I’ve ever grown was a great standby all winter. There were still edible stalks left, but the plants were thickening in the centre indicating that they about to throw up a flower stem. White butterflies were showing too much interest in the kale and the poor spinach plants were past their prime.

I could have got a few more meals off these plants, but I decided it was time to clear the decks to make room for summer crops. The soil has been refreshed with compost and sheep pellets.

I’ve planted a few radishes, spring onions and lettuces but left plenty of room for successive plantings of salad greens so that I’ll have a steady supply over a long period rather than everything ready at once.

Keep on top of regular jobs

Try to do a couple of small tasks every day so that you aren’t faced with a daunting to-do list on the weekend. Breaking up big jobs into several small tasks makes the work feel more manageable.

There’s no need to weed the entire garden in one go – spend 10 minutes weeding around the garlic and shallots today (they’ll grow much better without competition) and tackle another bed tomorrow.

Spending time in the garden each day helps you spot problems before they get out of control.

• Aphids on new rose leaves or broad beans? Squish with your fingers or wash off with soapy water.
• Caterpillars on the brassicas? Squash caterpillars and flick off the eggs with a paint brush. Cover plants with insect mesh to prevent more eggs being laid.
• Rusty mint? Cut back to ground level. Healthy fresh leaves will grow back in time to flavour your new potatoes.

But don’t concentrate on the problems. Take time to spot what’s coming into bloom, enjoy the scents, bird song and fresh air on your daily tour of the garden.

Plant an avocado tree

Love smashed avocado on toast but wince at the price? If you live in a warm part of the country, have a spacious garden and well-draining soil you could grow your own. Choose a warm, sheltered position for your valuable avocado tree. The site should be protected from wind and be warm and sunny. Avocado trees are salt-tolerant so can be grown in coastal locations. The best time to plant is in late spring when the soil temperature is rising and there’s less chance of wet feet.

Avocados have male and female flowers and different varieties open the male and female flowers at different times of the day. Most avocados will need a pollinator tree nearby, or you can buy grafted trees with a couple of complementary varieties. Careful choice of varieties could give you avocados nearly all year round. For information about varieties and fruiting times, see Incredible Edibles.

If you only have a small space but long to grow your own avocados, you could try the close-planting method of four or more mini trees described at AvoPro. Growing several varieties together keeps the trees small and also provides cross pollination which helps avocados set, and hold, more fruit each season.

Off with their heads – tough love deadheading

It takes determination to snip off the last brave bloom still flowering when all its neighbours are dead or dying but a ruthless short back and sides when deadheading perennials does look better in the long run.

The plant will have a balanced shape and the next flush of flowers will synchronise with each other as shown by the Federation daisy on the right.

Alternatively you can stagger flowering over a longer period but cutting back different parts of a plant (or individual plants within a mass planting) to different heights. This looks more natural for plants in a border rather than a stand-alone feature plant in a pot.

Note this advice is, “Do as I say, not do as I do”. I’m rarely hard-hearted enough to go in for the chop when a flower could last another day or two.

Gardening by the moon

The fertile period continues until October 19. Sow and transplant leafy crops. Sow out of doors if the soil temperature is sufficient – peas, bush and climbing beans and all the brassicas. Don’t prune. From October 20-23 stop planting – weed, cultivate and prune instead.

Gardening by the maramataka

Kōanga (spring) has arrived. Whiringa-ā-rangi is the fifth month of the maramataka and the traditional time for final land preparation for crops.

We should now be fully immersed in the emergence of spring following the flowering cues of specific trees and bushes such as the tī kōuka (cabbage tree).

At this time of year, it is not only plants that reawaken: insects and animals such as manu (birds) change their behaviour and provide us the impetus to get outside and prepare.

For summer crops, this is the time to open the ground, turn the soil to expose it to the warmth of the sun and to allow nature to assist in pest control. Birds will gravitate to feed on beetle and moth larvae.

In the very north, this month represents planting by the second week at latest. This timing will be later – maybe even next month – as you move south.

Soil temperatures matter and reading the soil through the return of new grass growth or emergence of spring weeds such as pōhue (convolvulus, native and introduced), huainanga (fat-hen) or amaranthus (morewhero) give a sure sign of the soil’s readiness to support spring cropping. Dr Nick Roskruge