May growing guide
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May is a lovely time of year, made for gardening. Gone are the long hot days of summer, replaced with warm, sunny days and cool, crisp evenings. It’s great gardening weather and your last chance to plant, fertilise and prepare before winter really starts to hit.
Veggies
Right now, it’s all about being self-sustainable – and that means growing your own edibles where you can, whether from seed or seedling. May weather is perfect for planting asparagus, broad beans, broccoli, cabbage, potato, rhubarb, rocket, spring onions, strawberries and winter varieties of lettuce. All of these can be grown really easily in containers – you can even grow potatoes in a hessian sack!
Peas should also be somewhere near the top of your planting list. All types – shelling, snow and sugarsnap – can go in the ground now. Don’t worry about planting in punnets. Just push the seeds straight into prepared soil, water well and you should see some shoots in a week or two. Watch for snails and slugs, though, as they love the shoots as much as you do.
Take your patch from drab to fab and plant out some purple vegies. Purple broccoli and cauliflower, red Russian kale, purple carrots and peas and coloured cabbages are good to grow now.
Leeks are easy to grow and delicious to eat. They're especially good for people who find onions and garlic too strong, but still enjoy a milder onion flavour. Plant out about 5cm apart in rows 30cm apart. When the leeks are a reasonable size, remove every second plant to give a spacing of about 10cm. These slender leeks are considered a gourmet treat. The rest of the leeks are left to mature (this can take 6 months), and stems can be covered with pipe or a milk carton to make them tender and white. Leeks do best in fairly rich, fine, loose soil with a pH between 6.5 and 7, and like an open, sunny, well-drained position. Make sure they thrive by digging compost or well-rotted manure into the soil before planting. Mulch to keep weeds under control but keep the mulch back a bit from the stems.
What to plant in the veggie patch
Broad beans, burdock, cabbage, carrots, chicory, chives, endive, garlic, Jerusalem artichoke, kale, kohl rabi, leeks, lettuce, mangle-wurzel, mizuna, mustard greens, onions, oregano, pan choy/ bok choy, parsley, peas, snow peas, radish, rocket, salsify, shallots, silverbeet, spinach, swedes, turnips and salad greens.
Fruit & trees
Winter is planting time for bare root fruits and ornamentals, so get your soils prepped now by digging through lashings of aged composts and manures.
Plants need haircuts, too, and the cooler weather is a great time for a quick snip. A lot of trees will be entering more dormant times over the next month or two so May marks a really good time for a healthy trim. You’ll be rewarded with new growth when it starts to warm up.
If you want to plant some citrus trees you are not too late. Citrus trees, and trees in general, really like to be planted in autumn. That way, they receive a good mix of sun and rain so that they can really develop their root systems, then get the rains of winter before they have to cope with the hot sun of spring and summer.
Feeling snacky? Pull on some gloves, it’s time to harvest chestnuts. Ripe nuts fall to the ground, so collect those with open burrs and no signs of pest damage. Refrigerate immediately, or roast and enjoy!
Attractive, vigorous and brilliant for brewing beer, hops can be planted now in warm temperate gardens. Plant crowns in a sunny spot, ensuring they have a strong climbing frame.
Natives
There is nothing sweeter than the winter scent of Boronia megastigma, so give one a go at home. These fast-growing natives do well in pots in protected, partly shaded spots.
Keep an eye out for the glorious autumn colours of Kangaroo Grass. Bronze, rusty and red, this native grass is an awesome ornamental.
Bring some biodiversity to your backyard and find a spot for a nesting box. Many bats and birds rely on tree hollows, so a well-placed nest box can make a huge difference in urban areas.
Grown all over Australia, Grevilleas are fuss-free, native shrubs that flower profusely! They come in a great range of sizes, from ground covers and mid-sized shrubs to tall screening plants, which are perfect for privacy. Their year-round flowers are also simply irresistible to native birds and insects. These beauties need well-drained soil and are sun lovers, so plant in full sun and keep sheltered from strong winds.
Flowers
May is your last chance to get spring bulbs in! Try and get them sown within the first two weeks of May for best results this spring.
Fill your garden with colour courtesy of ageratum, alyssum, aquilegia, calendula, Canterbury bells, cineraria, coleus, cornflower, delphinium, everlasting daisy, hollyhock, impatiens, larkspur, lobelia, pansy and primula. These guys are great at attracting pollinators and beneficial insects to your patch, and the flowers look good as well.
Think ahead and trim lavender now for spring flowering, ensuring you don’t cut into the hardwood.
Finish trimming hydrangea flower heads for a striking and long-lasting cut flower display. You should also prune your plant to a set of two plump buds, ready for the next flowering season. Again, don’t cut into the hardwood! If you want to change their colour, apply lime for pink shades or Hydrangea Blue for blue shades - it's much too late when flowers start budding in December but do it now and you’ll reap what you sow!
You can start pruning your roses in May, however, I recommend you wait until June or July. Other shrubs and hedges that have completed flowering could handle a healthy trim, bringing them back inline and into the shape you desire them to be.
Now that dahlia foliage is failing, it’s time to cut any remaining leaves off at ground level. If soil is well drained, leave tubers in the ground, otherwise lift and store in sawdust.
Pest watch
If you’ve planted brassicas, such as broccoli, cabbage, cauliflower, turnips or pak choy, you might notice cabbage white butterfly caterpillars leaving a trail of destruction. Sling some sage in with them as this incredible edible is not just delicious, it’s a cracking companion plant. It’s great at keeping the cabbage white butterfly at bay. Land cress also works brilliantly as the butterfly prefers to lay its eggs on it instead of your brassicas.
Keep snails and slugs away from bulbs, annuals and seedlings with animal-friendly organic pellets, beer traps or coffee grounds.
Check indoor plants for scale infestation and treat with an organic pest oil if found.
Spray fruit trees such as apricot, plum, peach and nectarine for brown rot with lime sulphur. Remove diseased leaves and fallen fruit.
Everything else
May is also the last month to get your plants ready for winter. If you have a lot of delicate plants in pots out enjoying the summer and autumn sun, now is the time to find a more sheltered spot for winter. Many pot plants are fine outside during winter but make sure your pots have good drainage, you don’t want the roots to be soaking in water 24/7 as this can cause the roots to rot. Potted plants do need a good amount of water, which self-watering pots do well, but they also need to have good drainage.
Make use of the fallen autumn leaves around your garden. Pile them up together in a compost bin or a corner of your garden so that they can break down and then be used as mulch. Some of the best gardeners I know spend very little on mulch because they use the natural seasons their garden goes through and the waste produced (such as leaves) to produce good, rich mulch themselves.
Winter rains are on the way, so get into your gutters and give them good clean out. Keep the leaf litter for your compost, or stockpile for lovely leaf mould.
Get warm and work on your lawn, which will set it up for summer success. Remove thatch with a rake, top-dress and patch depressions, and oversow thin areas of turf.
Many carnivorous plants are now going into dormancy. Give them less water, leaving the soil only slightly damp, which allows them to rest and recoup before a burst of spring growth.