What to do in your garden: March

Our experts share their seasonal tips so that you can add them to your to-do list this month, no matter where you live!

Photo: iStock

Countrywide, summer crops are ending, which signals the time to get cool-season crops on the go. Let’s get started!


After wet-season leaching, soils and microbes are hungry, so give them a boost with rock minerals, trace elements, compost, aged farm animal manures and worm castings, then lightly fork over. Water soil with diluted molasses and seaweed extract, then mulch.

Collect rotten, diseased fruit and leaves. Bag and bin them or bury at least 1m deep.

Grow tomatoes in big pots. Pre-water seedlings with diluted seaweed extract. Fill the pot halfway with quality potting mix, then add a sprinkle of rock minerals, chicken manure pellets, dolomite and worm castings. Fill with more potting mix, make a well and plant Mulch then water with diluted seaweed extract.


Keep a garden diary. Record seed planting dates, note rainfall, weather conditions, pests and diseases, good bugs and birds, what you harvested, fertilisers used.

Before sowing beetroot seeds, freeze for 12 hours, then soak in diluted seaweed extract for one hour. Sow direct into well-drained, compost-rich soil. Water fortnightly with diluted seaweed extract.

To make compost tea, three-quarters fill a bucket with roughly chopped comfrey and weeds, then fill with water. Seal with lid. Stir every day for four weeks. Dilute the tea liquid with water at a 1:10 ratio.


Bean podborers (bean caterpillars) are tricky to manage because they start inside the flowers before moving into the pods. Tell-tale signs are frass and webbing. To control spray early and thoroughly with a Bt (Bacillus thuringiensis) spray.

It’s easy to forget bomb-proof fig trees while you’re coddling fussier plants during dry spells, but a little regular watering produces larger, more luscious fruit. A good soak after harvest will improve next year’s crop.

It’s an ideal time to plant trees and shrubs while the soil is still warm.

Warm Temperate

Cooler weather signals time for peas. Sow seeds directly where they are to grow in a compost-rich soil. Protect young seedlings with a copper collar or other snail deterrent and provide a trellis for them to grow on.

Prune grey-leafed plants such as lavender and santolina. Cut them back at the base of the flower stems at the same time as tip-pruning the leafy stems and shaping the bushes.

Control scale insects by using soapy water and a toothbrush to scrub them off. For larger infestations, spray with pest oil in the evening to coat the stems and leaves.

Cold Temperate

Plant spring-flowering bulbs such as bluebells, daffodils, freesias, hyacinths and tulips in attractive pots. Plant bulbs, water and keep moist, but not wet. When shoots start to appear, add pelletised organic fertiliser.

Dig, divide and replant perennials such as bergamot and catmint. Dig the whole clump, then use secateurs to break it up. Work compost and well-rotted manure into the garden where you are replanting and replant a few clumps.

The first autumn rains bring out the snails. At this time of year they are carrying hundreds of eggs. Hunt them out in their hiding places and drop into soapy water to kill.


First published: October 2019

Related topics

Gardening Basics, All Gardens, What to do now