What to plant in May | In the Green Room

May is prime time to plant those leafy vegetables like cabbage and lettuce. Photo: iStock.
May is prime time to plant those leafy vegetables like cabbage and lettuce. Photo: iStock.

The autumn weather is in full-swing, and now is the perfect time to sow those plants that like a bit of cold and wet to get off to a good start.

In the southern part of Western Australia, this time of the Noongar calendar is called ‘Djeran’.

Cool nights bring in dewy mornings, and the first rains start to fall. 

There’s a wide range of vegetables, fruits, natives and flowering classics that can go into the ground now. The damp soils and milder temperatures gives roots and new leaves plenty of time to establish before plants start getting sexy in spring.

Vegetables

Rainbow carrots bring a splash of colour to the kitchen table. Photo: iStock.

Rainbow carrots bring a splash of colour to the kitchen table. Photo: iStock.

May is the time to plant leafy and root vegetables, as well as peas and beans. This late into the season you want to be planting seedlings and young plants, rather than sowing straight from seed.

In sandy, coastal areas, it’s essential to ensure the veggie patch is prepared before you put anything in the ground: the more work you put in now, the less you’ll have to do over the coming months.

Mix a bag of compost into every two square metres of existing soil to a depth of about 50 centimeters.

If you’re closer to the coast and your soil is sandy, it may also be a good idea to add gardening clay, which will help with water retention.

Plant each seedling with a pinch of slow-release fertilizer in the hole, and apply snail pellets to the area when you’re done.

> May vegetable checklist:

  • Leafy veggies: artichokes, brussel sprouts, cabbage, cauliflower, broccoli, lettuce, leeks, kale, cabbage
  • Root veggies: carrot, radish, beetroots, turnips
  • Legumes: sweet peas, broad beans, lima beans, French beans, garden peas, sugar snap peas, Borlotti beans
  • Herbs: parsley, chives, oregano, sage, rosemary, thyme

Fruit

Though they look bare in winter, these healthy fruit trees promise a delicious crop in the warmer months. Photo: iStock.

Though they look bare in winter, these healthy fruit trees promise a delicious crop in the warmer months. Photo: iStock.

Autumn is the best time to plant stone fruit and nut trees. They may look bare and twiggy, but that’s excactly what you’re after: planting them before they shoot or bud gives them time to settle into the ground or pot before growing season.

Many bare-rooted trees will become available in nurseries at this time of year.

Ideally you want a tree with roots and branches about the same size, and with no visible damage (dark patches or lesions on the bark). Don’t be afraid to trim back the branches so they are equal to the size of the roots. Balance will put your tree off to a good start.

Bare-rooted trees can be much less pricey than their potted counterparts, though potted trees are also fine to plant in May. The main thing to be aware of when planting trees is to get the depth right: too shallow and the roots will be too exposed; too deep and you’ll get collar rot.

You’ll notice a slight change in colour right at the base of the tree. That’s where you want your soil depth to line up.

The same soil preparation advised for growing vegetables will suit fruit trees, however they will also benefit from some chunky mulch. Make sure not to pile the mulch up around the trunk of the tree (to avoid collar rot). Instead, form a ring around the ‘drip line’ about the width of the branches, leaving a little moat between the ring of mulch and the tree’s trunk.

>May fruit tree checklist:

  • Apple trees: Pink Lady, Gala, Granny Smith, Jonathon, Golden Delicious
  • Stone fruits: nectarines, plums, apricots, peaches
  • Nuts: Almonds, walnuts, chestnuts
  • Other fun things to try: blueberries, quince, pomegranate

Natives

Most community groups that do revegetation do their planting in late Autumn, because it’s the perfect time for native plants to establish.

Though native plants are notoriously hardy, in their early days they must not dry out, or they will die.

So the aid of autumn rains and cooler weather puts them off to a good start.

>May natives checklist:

  • Small plants and shrubs: Coastal rosemary (Westringia dampieri), Grey cottonheads (Conostylus candicans), Kangaroo paws (Anigozanthos sp.), Grevillias, Pink rice flower (Pimelia ferruginea), Bookleaf (Daviesia cordata)
  • Vines and creepers: Happy wanderer (Hardenbergia violacea), Coastal pigface (Carpobrotus glaucescens), Coral vine (Kennedia coccinea)
  • Large shrubs and trees: Pincushion hakea (Hakea laurina), Bull banksia (Banksia grandis), Candlestick banksia (Banksia attenuata), Menzies banksia (Banksia menziesii), Jarrah (Eucalyptus marginata), Marri (Corymbia callophylla)
  • Bush tucker

Flowering perennials

Azaleas may be a little high-maintenance, but their lurid blooms have an addictive appeal. Photo: iStock.

Azaleas may be a little high-maintenance, but their lurid blooms have an addictive appeal. Photo: iStock.

> Roses

It’s a good time to plant roses and often this time of year you’ll find them on special because they’re at the end of flowering or else already pruned. Prepare the soil by mixing in plenty of cow manure.

For existing roses, give them one last feed before they go into winter dormancy.

It’s also a good time to treat roses for fungal infections like black spot and powdery mildew, either with store-brought fungicide spray or make your own by mixing 2 litres of water with 1½ tablespoons of baking soda, 1 tablespoon of vegetable oil, and a drop of detergent.

> Azaleas and gardenias

These horticultural classics need an acidic soil. May is a good time to get them into the ground because, originating from much wetter places than here, they will have time to settle in and establish their roots before the hot weather returns.

Because most of Western Australia has alkaline soil, your best bet for growing azaleas or gardenias is in pots, or raised garden beds, where you can build up potting mix and compost to get the pH just right.

Avoid planting them anywhere near a limestone wall, or places you know the topsoil is shallow.