Most of Australia has just emerged from the awful El Nino drought. Our garden plants have suffered badly through this period. So, this is the most important spring in the last 10 years – put in some effort now and the results will be tremendous.

The problems:

After the drought many tree roots will have died off and more trees than usual may fall over.
Equally, many shrubs are in a very poor state.
Borers and wood rot will have gotten into trees during the drought. Dry conditions cause cracks in trees and shrubs which permit easy entry for borers and wood rotting fungi.

What To Do

Fortunately the prognosis is good. If you fertilise now with a complete fertiliser, the plant’s natural defences will overcome most of the problems. Don recommends putting Seasol on everything. It is the magical cure-all for tree problems in particular. As well, fertilise natives with Osmocote or Nitrosol, fertilise citrus with citrus food, fertilise the lawn with Scott’s slow-release or Dynamic Lifter Greenkeeper’s Choice. Senile trees and shrubs should be removed (don’t forget Council approval for sick tree removal).

Areas of the country which are still experiencing dry conditions, forget the above. Simply water plants as well as you can. Do not fertilise the plants during a dry period as this may cause further root problems. Just batten down the hatches and wait for moisture.

But please be aware that this is a critically important spring. Put in lots of effort now even if you didn’t for the past 10 years and don’t intend to for the next 10.To help you do this, Burke’s Backyard has prepared a ‘Spring Garden Care Guide’, containing all the information you need to know to get your garden in shape for the next decade.

Spring lawn care check list

Fertilising the lawn

Use complete lawn foods for best results such as: Dynamic Lifter Greenkeeper’s Choice (a mixture of Dynamic Lifter and a fortified lawn food); Scott’s Lawn Builder, a slow-release fertiliser; Shirley’s Lawn Food No 17; Osmocote; Yates Weed and Feed – a handy method of feeding and ridding the lawn of Kurnell curse or pennywort (Hydrocotyle tripartita), in buffalo or kikuyu lawns. Do not use sulphate of ammonia (it greens but is not a balanced fertiliser). Note: for best results, test the lawn pH before fertilising.

Acid soils and lime

If your soil is too acidic (pH 5.5 or less) your lawn will have difficulty in absorbing nutrients for growth. Do a pH test. The optimum pH for lawns is between 5.5 and 7.5.

If soil pH falls below 5.5, add lime or dolomite to raise its pH. With time and the addition of lawn foods, most soils will become more acid.
If your soil pH is above 7 you can apply iron sulphate at a rate of a handful per square metre to lower the pH. Most Australian soils are acid but there are some exceptions, such as sandy soils derived from limestone (around coastal Perth, Adelaide or Bondi Beach in Sydney).

Raising pH

Adjusting the pH is easier on loamy and sandy soils than on heavy clays. If your soil is a sandy loam and you need to raise the soil pH by 1 unit from, say, 4.5 to 5.5, add the equivalent of 150g of liming material per square metre. An adult handful is about 100g. Heavy clay soils will require at least 250g to raise the pH by 1 unit.

A superfine grade of lime works quickest and is the best choice. Omya Superfine Lime is available from Elders Stockmans nationally for $6.95 per 25kg.
For an established lawn, which may be lacking magnesium, mix 50:50 lime and dolomite as the liming material to get the right balance of calcium and magnesium. Dolomite is only available in one grade and costs $6.95 for 25 kg.

Tip: after applying lime or dolomite make sure you water it in well so that it moves into the soil.

Burke’s Backyard pH Kit is available from Burke’s Backyard for $15.50 (including postage and handling) and will accurately tell you the pH of your soil. One kit will last for years and do many tests. To test pH take about a teaspoon of soil and place it on the white tile in the kit. Add a few drops of indicator on the soil and then puff a small amount of the white powder over the soil. Make sure that you have covered the moistened sample but don’t drown it in powder because the powder has its own acid pH. Compare the colour with the colour chart. By the way, colour-blind people will not be able to get a proper reading.

Beating soil compaction

Soil compaction caused by continuous traffic (such as walking, cars, kids playing) prevents air getting into the soil and leads to poor lawn growth (no matter how much fertiliser you pour on). Weeds such as bindii and other broad-leaved weeds take over. Test compaction by pushing a garden fork into the ground. In a good lawn the fork should easily go down half way or more. If it doesn’t, the lawn is compacted and needs fixing.

Solutions: pave heavy traffic areas (such as the track to the clothesline, as grass will always have trouble growing). Aerate compacted lawns with a garden fork or a power aerator or coring machine. These can be hired from equipment rental companies for about $115 per day.

Top dressing

Top dress uneven lawns or lawns with holes. Don recommends using river sand, rather than commercial top dressing mixtures. As well as levelling the lawn, the sand layer under the grass provides excellent drainage. Use a lawn leveller to spread the top dressing. Quality lawn levellers are available from good hardwares or garden centres for about $100. After top dressing give the lawn an hour and a half soaking with a hose or sprinkler.

Weeds

After the long drought many lawns look terrible. Where growth was thin and weak, weeds have taken over, particularly bindii. It’s not too late to knock out these weeds using a herbicide such as Chemspray Bin-die or Yates Bindii (avoid products containing Dicamba which can be absorbed by shrubs and trees). Spray on a still morning and use some cardboard to shield plants near the edge of the lawn from drift. These herbicides can damage any plant that isn’t grass. The first grass clippings after spraying should never be placed around plants as a mulch (leave them on the lawn).

Handy fertiliser guide

In the wild, plants are nourished by a constant diet of decaying plant and animal matter. But in the artificial environment of the garden, plants need to supplement their diet with fertilisers. Spring is the time to fertilise all your garden. Fertilisers are divided into two main groups:

Organic fertilisers, derived from plant and animal products. These include manures, compost, blood and bone and Dynamic Lifter.
Non-organic fertilisers, usually sold in granular or powdered form. Within these two groups are many different formulations including fertilisers for specific plants (such as roses, citrus and the like) and all purpose fertilisers. Despite the enormous range of fertilisers available, the average garden only needs about five basic types of fertiliser: a complete lawn food; Dynamic Lifter; citrus food; liquid food (Nitrosol); and slow-release (such as Osmocote).

Citrus fertilising

Mid spring when citrus crops are finishing and new growth is appearing is the time to fertilise citrus. As they are similar in composition to rose foods, citrus food can be fed to roses and vice versa. Citrus and rose foods can be used to fertilise vegetables, too. Chook poo (such as Dynamic Lifter) is a also good for citrus. Alternate between citrus food and a general fertiliser such as Dynamic Lifter. Use one in spring and the other in late summer.

To fertilise a full grown citrus tree spread about 1.5-2 cups of fertiliser, such as Yates Gro Plus Citrus Food, under the tree to the drip line, where the feeder roots are found. The drip line is the line of the outer edge of the branches where the drips from foliage would fall. Water well after applying fertiliser. Citrus in tubs need small amounts of food frequently. Either fertilise every 4-6 weeks from spring to late summer with a small amount of Dynamic Lifter or citrus food, or use a slow-release fertiliser such as Osmocote Plus.

Fertilising native plants

Care must be taken when fertilising Australian natives, because too much fertiliser, particularly products high in phosphorus, can kill them. Natives are hardy in most Australian soils, so if they were never fertilised, it probably wouldn’t matter. Recommended fertilisers are blood and bone, Dynamic Lifter (not fortified Dynamic Lifter) and formulations of slow-release fertiliser for native plants. Do not use very much: a light handful over a few square metres is sufficient.

Fertilising vegetables

Most general fertilisers can be used on vegetables but complete plant food is particularly useful. Apply manures and complete plant food to soil when it is being prepared for planting. Liquid feeds can be used on vegetables. These should be used to promote vigorous growth by making frequent applications to crops while they are growing. Don’t forget to check the pH of your vegie patch. The ideal range is 6-7.

Fertilising pot plants

Fertilising plants growing in pots is crucial because they grow in potting mix which becomes depleted of nutrients. Slow-release fertilisers such as Osmocote and Nutricote are recommended for pot plants. Apply a 9 month formulation in spring. As well, apply Nitrosol (liquid food) to give a quick boost before the slow-release fertiliser becomes active (2-3 weeks). Nitrosol is a liquid form of blood and bone which was developed in Australia. Use one capful of Nitrosol to the average watering can.

Fertilising orchids

Orchids respond well to fertiliser at the right time. Many growers swear by Campbell’s Orchid Fertiliser. This comes in two forms, one tailored to encourage flowering and the other for growth. Orchids can also be fertilised with a gentle liquid food such as Nitrosol or with Dynamic Lifter.

Fertilising a big tree

Garden trees, particularly native trees, need care and attention to stay healthy and safe. A tree in your backyard is under a lot of stress compared to the same species in the bush. The backyard tree may have soil built up over its roots, lawn near its trunk, concrete paths nearby and other plants competing for water and nutrients.

Evidence of stress include borer attack such as bull’s-eye borer (caused by the larvae of one of the longicorn beetles). Borer attack is a sure sign of stress as a healthy tree would be able to repel such an attack. Signs to look for include holes in the trunk or branches (especially holes that look like a bull’s-eye), oozing gum, a build-up of frass or fine wood shavings, or die-back of branches.

To treat stressed trees and help them repel insect attack apply Seasol around the feeder roots of the tree (between the trunk and the drip line). To apply, use a garden fork in the soil to make a series of holes. Do not go closer than a metre to the trunk and create about 20-30 holes around a medium sized tree. Seasol (available at nurseries and produce stores) can help to invigorate the roots, possibly by encouraging the growth of beneficial soil micro-organisms. Apply Seasol regularly for several months before any fertilising is done. Once the tree is starting to respond to the Seasol treatment, apply an organic fertiliser such as Dynamic Lifter, blood and bone or slow-release tree tablets.

Note: Sadly, some trees will be damaged beyond repair. Trees which have not survived the drought well should be assessed by a qualified tree surgeon and removed if they are in danger of falling over and causing serious damage. To contact a qualified tree surgeon look under ‘Tree Surgery’ in your local Yellow Pages. NB: Council approval must be gained before any tree is removed.

Safe garden pesticides

Roses: if you choose to grow roses then you are choosing to spray. Rose problems include black spot (seen on leaves as black spots surrounded by yellowing); and powdery mildew (white powder on leaves).

Solution: Triforine (mix up yourself) or Baycor (available in a spray can). Roses also suffer from aphids, thrips and spider mites (twospotted mite) and occasionally caterpillars.

Solution: PestOil or Mavrik.

Azaleas: as azalea flowers open they can get petal blight which causes flowers to go brown and rot on the bush.

Solution: Bayleton (applied at weekly intervals during the flowering season). Insect pests such as spider mite or lace-bug, seen as silver discolouration of the leaves, also attack azaleas.

Solution: PestOil applied from October to April.

Lawns: a well maintained lawn is less at risk. But one persistent problem is lawn beetle.

Solution: while the larva stage is difficult to control, the adults can be flushed to the surface (from October to November) with Baythroid Lawn Beetle Killer.

Citrus: Solution: feed spring and late summer and treat leaves from January to March with PestOil. For bronze orange bugs or stink bugs, cover up with gloves and sunglasses and pull them off by hand.

Ants, cockroaches, fleas, flies and mosquitoes: many chemicals used around the garden are not safe with birds.

Solution: if you’ve got birds in aviaries, poultry or livestock, use Coopex (available at specialists and rural produce stores).

Slugs and snails: if you keep dogs, be careful as snail bait is toxic to dogs. It can also harm lizards and native animals.

Solution: hand collect snails or use Baysol (never put it in mounds where animals can eat it) and collect dead snails daily.

citrus leaf curl (also known as citrus leaf miner) or other common pests such as scale, bugs and mites all attack citrus.

Safe use of pesticides

only buy the smallest amount necessary
read and follow the directions on the label
only spray during the cool and calm of the day
store in the original container in a locked cupboard
wear protective clothing

Where dry conditions continue

Although many areas have had lots of rain, the drought is continuing in some parts of Australia. For these areas:

Delay fertilising (particularly lawns) until good rains are received.
Mulch around all plants (7-10cm or 3-4″ thick). Use an organic mulch.
Deep water gardens (including trees) at least once a week using a sprinkler (unless prohibited by local restrictions).
Use a soil rewetting product. Prolonged dry conditions may also affect the soil’s ability to absorb water. Saturaid (from Debco) and Wettasoil are rewetting agents. When added to the soil they encourage moisture to penetrate the soil more readily and allow it to hold more water.