Garden tasks for June 2015

Flower garden

You’ve still got time to plant lilies in an area of well-drained ground.

F-JN15-Garden-Monthly.jpgPrune climbing roses later this month, and also ornamental trees and shrubs. Don’t prune spring-flowering shrubs until they have finished blooming, and prune your deciduous trees in dry weather.

June is also a good time to shift poorly-sited trees, shrubs, perennials and roses.

Perennials such as asters, achillea, dahlias and phlox can be cut back, lifted and divided.

Prune hydrangeas and thin out all weak growth. Use lime to improve pink colours, and aluminium sulphate for blue.

Plant your new roses in well-prepared ground, and ensure young trees and fragile plants are firmly staked and tied.

This month is a popular time for planting hedges, both evergreen and deciduous. Choose smaller plants, and plant closer together, rather than fewer larger ones, if you want the best and quickest end result.

Sow seeds of lobelia, calendula, sweet peas, dianthus, sweet William and alyssum.

Plant out seedlings of pansies, viola, polyanthus, Canterbury bells, alyssum, primula, hollyhock, cyclamen, honesty, lobelia, sweet pea, poppy, anemone, candytuft and bellis daisy. Use Quash to protect newly-planted seedlings from slugs and snails.

Fruit and vegetable garden

F-JN15-lemonPlant strawberries and new fruit trees such as citrus, apples, pears, plums, peaches and nectarines.

Strawberries are great for growing in pots and hanging baskets, and it’s also easier to keep those pesky birds at bay if you grow them on a sunny deck close to the house.

Prune deciduous fruit trees and protect cuts with pruning paste. Spray with Champ DP and Conqueror oil to protect from pests and diseases.

June is the traditional time to plant garlic and shallots. Choose a sunny, free-draining spot, and dig in some well-rotted compost. You can also grow both garlic and shallots in pots. Garlic needs a container at least 20cm deep and shallots 15cm deep.

Clean up old asparagus beds and give a dressing of manure. You can also prepare ground for new beds. Asparagus is usually available in garden centres around this time — plant crowns in well-drained soil.

Earth up your celery and leeks.

Sow seeds of spinach, silverbeet, peas, onions and lettuce.

Plant out seedlings of cabbage, cauliflower, winter lettuce, broccoli, silverbeet and spinach.

Lawns

Clear fallen leaves off lawns or they will smother desirable grasses and encourage moss to infiltrate.

Second thoughts

If you were given a potted chrysanthemum for Mother’s Day plant it outside once flowering has finished. It’s a good idea to harden your plant off first by putting it in a sheltered place for several days — maybe a covered deck or patio. That way the plant can begin adjusting to cooler temperatures outside before it has to cope with the full effects of winter.