Gardening ideas for June

June is also the time to prepare plants for winter shock. Even in balmy coastal areas, it can become bitterly cold so take precautions. Give beds exposed to cold westerly winds a thick layer of mulch, both from your compost heap and from newly fallen leaves to prevent surface roots drying out or bursting as they freeze. Any winter rain breaks down mulch and feeds roots.

There is still time to lift and divide summer blooming perennials. As you do this only every few years, enrich soil now with plenty of compost and manure. Discard old, woody centre stems. Replant only new shoots and runners from the outside of the clump.

Add colour to your garden this winter

Winter garden projects:

• clean all gutters before rain sets in;

• put leaves in compost bin, or spread around shrubs and trees

• form a new path, or install trickle irrigation.

If you let your vegetable patch lie fallow in winter, dig in humus and compost evenly. A bale of lucerne hay or straw spread evenly, sprinkled with lime and fertiliser gives a great start for spring planting, too. Water well and leave a few weeks before turning over.

Tropical zones:
Pruning is paramount to cut away untidy wood; correct bad shape; thin overcrowded branches.

In short, fix any condition lessening the tree's bearing capacity. Cut out any unwanted branch, so new branches growing in its place will face the right way to make a shapely tree and not cross other branches. Burn diseased wood at once. If timid about pruning, seek advice.

Cold zones:
Give the garden a good clean-up and check for wet spots. Raise beds to improve drainage.

Keep soil surface tilled to allow maximum water soakage, avoiding a heavy waterlogged surface. Ample mulch also helps by soaking up excess water.

Weed growth has stopped now, so condition soil.

When frost threatens, cover plants at risk or hose frost from leaves before the morning sun catches them. Do not trim damaged plants after October as pruning removes protection given by damaged growth and promotes frost-tender new growth.

Remove summer annuals and salad vegetables burned off by frosts and add to compost. Then give beds a generous dressing of compost or old farmyard manure.

Improve 'resting' garden beds by growing a green manure crop such as field lupins and dig in during spring.

Flowers

Allow dahlias and other soft-wooded plants such as herbaceous perennials to die off gradually in frosts. Towards the end of the month lift dahlias with soil attached to tubers. Store under a hedge, or `heel in' until they shoot in spring. Light covering of sand or soil protects against pests and prevents shrivelling.

Cut chrysanthemums to ground level. If you need garden space, lift plants with a garden fork, easing roots out gently. Put in a sunny resting bed in a quiet corner and leave until division time next year.

Violets are a winter joy. Make a border of violets or plant in clumps in a bed. Runners can be taken easily from a friend's garden. Contrary to belief, they flower prolifically in full winter sun. Before planting, add plenty of humus to good soil which has a ration of well-balanced fertiliser and a dusting of lime. Turn over 10-12cm and dig in well. If you have more leaves than flowers cut back leaves hard.

In tropical zones
The lovely, highly perfumed climbing oleander (Strophanthus grates) flowers now. Petals are burgundy outside and palest pink inside, variegated against shiny leaves. It can be trained up trees or through fences, or pruned into a shrub.

Hibiscus require continuous fertilising: 50g of a high-nitrogen mixture monthly or larger amounts (250-500g) of organic fertiliser such as well-rotted fowl manure or blood and bone. Lightly mix with soil around the leaf canopy. Regular watering is essential. Check with your local nursery before selecting hibiscus; some Hawaiian varieties don't last in this climate.

Roses

Plant new roses in a bed previously prepared. If the ground is not ready, heel bare-rooted plants into a spare bed to prevent roots drying out. Prune roses from mid-June to mid-July, later in areas where new growth could be damaged by late frosts. Trim spent flowers from winter flowering Lorraine Lee roses and prune these in March.

Shrubs and trees

Summer flowering shrubs such as abelia, crepe myrtle and fuchsia like gentle shaping. Prune Prunes nigra and Prunes blireiana from the inside like an orange tree so every branch is important - the result resembles a Chinese painting.

Shorten hydrangeas, not summer-pruned now. Prune only last summer's flower stems. Start feeding now until October-November with aluminium sulphate to promote blue bloom. Move any shrubs, up to 1m high, positioned wrongly in your garden. Shrubs transplanted easily include abelia, azalea, escallonia, Mexican orange (choisya) and veronica, not daphne and luculia.

Prune deciduous trees which have shed their leaves now that branch formation is seen. Seal cut with paint to prevent bleeding. Prepare holes for planting deciduous trees. Replace poor soil with a good loam mixed with rotted cow or organic manure.

Prune wistarias now they have lost their leaves. Take all climbing tendrils back to the first pair of side buds; you will get no blooms away from short lateral spurs.

In tropical zones
Prune mussaenda quite heavily now for Christmas display. Without regular quite severe pruning, it will become very straggly. Fertilise with blood and bone or well-rotted chicken manure mixed with soil around leaf canopy, or use a high nitrogen chemical fertiliser.

Trim native shrubs, removing old dead wood, and apply a handful of blood and bone to the smaller ones, two handfuls to larger shrubs. Gently rake in around shrubs, removing any weeds.

In cold zones
Azaleas and rhododendrons flourish in most cold areas in full sunlight or semi-shade (but not deep shade), in well-composted acid soil, well-drained and protected from wind. Their roots are shallow, so be careful not to hoe too deeply or add fertiliser close to the main stem.

Now is the time to start removing any tree you don't want. Some trees, too large to be dug out, are killed with herbicide, before or after being cut down. Drill several holes downward into the trunk about 20 mm wide and 60 mm long and fill with diesel fuel or kerosene. Cork the hole. You may have to repeat this before it finally dies.

Avoid aimless pruning. There is more harm than good in cutting back flowering shrubs in the hope of spring flowers. Most shrubs put out flowering wood at summer's end, so pruning now removes all the shrub's flowering preparation. To improve the shape or vigour of a shrub prune right after flowering.

Topdress alpine plants and cuttings with compost or stone chippings. A layer of straw over any hairy type of alpine plant will protect it from rotting in very wet conditions.

Bulbs

Cannas and ginger lilies can be cut back hard, and exposed roots covered well with mulch. Check caladiums which have died down. Tip out of the pot and if the bulb is large, cut into smaller pieces to increase the number of plants. As long as there is an eye on the piece of bulb, it will grow (rather like a seed potato). Repot the pieces, fertilise and water for new shoots.

In cold zones
Lift remaining gladiolus corms and store in a cool, dry spot. Weed beds of spring flowering bulbs, but do not damage emerging shoots. Protect new shoots of developing bulbs with a light layer of straw.

Topdress lily of the valley heavily with well-rotted compost.

Lawns

In cooler areas, couch or buffalo lawn may be aerated with a spiked roller or tamper. Oversow with mix of bent seed and fine sand. Sprinkle lightly but regularly for instant greening.

Fruit

Prune fruit trees towards end of month, burning or burying any mummified fruit or diseased prunings. Cover spray winter oil on pome fruits after pruning. Remove faulty growths from apple and pear trees, and shorten heavily fruit-laden branches likely to break.

Peaches and nectarines fruit on previous season's young shoots; prune accordingly.

Prepare sites for berries suited to your district. Into sandy soils work compost and peatmoss. Work decayed manure, compost and coarse sand into clay soils. On heavy soils raise beds 20cm to assist drainage.

Vaccinium corymbosum is highly shorten heavily fruit-laden branches likely to break. Peaches and nectarines fruit on previous season's young shoots; prune accordingly.

Blueberries, currants and gooseberries form a bush, while raspberries, youngberries, loganberries and kiwi fruit require a suitable support.

Old raspberry canes which bore last season's fruit should be cut as close to the ground as possible. Remove weaker canes leaving 10-12 new canes to each bush. Wrap canes together with heavy string, arch down and tie to supporting wire, leaving about 25cm extending beyond the wire. To keep canes at a comfortable height for picking, wire should be 1m above the ground.

Fertilise fruit trees with cow or sheep manure, keeping it away from stems. Four-year-old trees take up to 17kg; younger ones about 7kg.

In tropical zones
Dig between raspberry and gooseberry rows, incorporating manure and compost as you go. Shelter the tender shoots from frost and wind

Vegetables

Fruit trees can still be planted; dig a hole 1m deep and 60cm in diameter, filling it with compost, loam, manure etc. Prepare new beds for strawberries, digging in leaves, grass clippings or old fowl manure, making beds 15cm high to assist drainage.

Feed with liquid fertiliser fortnightly to maintain growth

In tropical zones
Prepare beds for planting potatoes next month. Use a rather light loam with plenty of added humus. Or, make a sowing of lupins and dig them in before they begin to wither. Also, spread a mix of two parts superphosphate, two parts bone dust and one part blood and bone along the bottom of the planting trench, 60g to 1m. Cover at once.

Potatoes need good drainage. Keep tubers billed up with earth taken out of the trench; this prevents tubers turning green and protects against potato moth. It is possible in most tropical areas to raise two potato crops a year, July and February. Increase food and water when flowering begins

In cold zones
Dig over the vegetable garden adding compost and manure to spring planting beds. Remove decaying leaves from brassicas and protect broccoli from frost.

More on Growing Vegetables

How to grow a vegetable garden
Companion planting
Easy to grow vegetables
How to grow tomatoes
Growing Tomatoes

Garden watch

1. Protect beds and containers of annuals from snails, especially on wet evenings.

2. Spray aphids and leaf miners on new growth of tender annuals with an approved chemical treatment.

3. Spray derris dust on all members of the cabbage family with leaf damage from caterpillars. Rain will wash the dust away, but dose again afterwards.

4. Winter grass in lawns can be removed by hand before it seeds - or spray with herbicide.

In tropical zones:
To control white scale on roses, spray with white oil emulsion diluted according to instructions on the container. Use gloves when shifting pots in the shadehouse to avoid spider bites. Clean mould from glasshouses, using a caustic solution, then spray with fungicide.

In cold zones:
Spray fruit trees every month with white oil for scale and an approved chemical treatment for aphids.

More on winter gardening

Colourful winter garden
Gardening ideas for June
July in the Garden
August in the garden