Coming out of winter, most lawns look a little worse for wear as a result of cool to cold soil and air temperatures which don’t encourage vigour and fewer hours of sunlight especially in southern Australia.
The most popular lawn grasses grown in this country are “warm season” types. They have been selectively bred to grow best in moderate to warm climates, but will still do reasonably well as far south as Tasmania and at altitude in the cooler mountain regions of Victoria and New South Wales. While our winters are comparatively mild, low night time temperatures slow the growth rate of lawns and, when low enough, can damage their roots.
Browning of grasses and thinning are common problems, making bare patches and high traffic areas look worse than they actually are.
In regions where most of the year’s rainfall occurs in winter, poor drainage and lack of soil aeration may cause lawns to turn yellow – not a pretty sight for any lawn-lover!
On the positive side with spring in the air, more hours of sunshine and warmer temperatures, the lawn is about to put on a burst of lush, green growth.
The key to spring rejuvenation of the lawn is not to start too early. Wait until at least mid to late September, when days are longer, the sun warmer and nights less likely to be frosty. If you encourage vigorous new growth too soon in the season, it may be damaged by late frosts or even snow if an Antarctic blast makes its way northwards.
Tips for lush, green lawn this Spring
Apart from allowing nature to improve the overall appearance of your lawn, there’s quite a list of tasks that you can take on to make the most of your expanses of green grass.
De-thatching the lawn
Using a steel pronged garden rake, go over the lawn vigorously to remove garden debris and, importantly, strip out dead and brown grass ("thatch") to allow more direct sun through the sward (expanse and depth of the lawn) to the soil surface. This will encourage new shoots and invigorate older growth.
Aerating the lawn
Aerate the lawn after de-thatching, to allow air, moisture, fertiliser and warmth to penetrate into the soil around the roots of the lawn. There are several aeration options available, depending on the size of your lawn.
- A coring machine, which can be hired from any one of the major equipment hiring companies, makes rapid work of removing plugs of soil but is only practical for larger lawns.
- A sturdy pronged garden fork is perfect for a medium sized lawn. Work across the area in rows about 300mm apart, pushing the fork about 150mm into the soil and “wriggling” it back and forth at each insertion. This will leave holes without removing plugs of soil.
- Strap a set of lawn spikes on to your boots or shoes, and go for a walk across the lawn! This method produces smaller holes but if you are thorough, lots of small holes will do as good a job as fewer larger holes in allowing air and fertiliser into the root zone of the lawn.
Topdressing the lawn
If your soil is particularly heavy, poorly drained, compacted or the lawn surface is uneven, topdress the entire area after aerating it. Use a premium quality topdress mix or washed river sand and work it into the lawn with the back of your rake. Follow the instructions on the bag for how much to apply. Any hollows over the lawn can be filled gradually by adding the recommended depth, allowing the grass to grow through completely, then repeating the process until the dips have been completely eradicated.
Fertilising the lawn
Mid spring is the best time to give your lawn a balanced, slow release feed. An average soil temperature above 15 degrees is needed for nutrients to be released from the granules and taken up by grass roots.
Fertilising in late September – early October gets the lawn growing strongly so it can power into summer. If you only fertilise the lawn once a year, now is the time to do it!
Healthy lawns on reasonably good soils will benefit from an application of Lawn Builder All Purpose or Lawn Builder Buffalo. If your soil doesn’t absorb or hold moisture well, then use Lawn Builder + Wetting Agent instead.
Grubs and other insect pests can be problematic in some lawns, most often in warmer climates. Where they are known to occur, the spring fertiliser application should be Lawn Builder Grub + Insect. It combines the benefits of a premium slow release lawn fertiliser with a safe and effective contact insecticide that will knock lawn pests for six.
Lawn Builder slow release fertilisers will provide a steady supply of nutrients for up to 10 weeks. We do not recommend re-applying before at least 8 weeks from application. If your lawn needs a quick pick-me-up before the next application of slow release fertiliser is due to go down, use either Lawn Builder Extreme Green hose-on or Lawn Builder Buffalo hose-on. They are readily absorbed and go to work immediately.
Watering the lawn
Spring can be an “awkward” time of the year when it comes to watering. The days may be bright, warm and sunny but the nights cool, maybe even frosty. It could be easy to assume that, because of daytime conditions, the lawn should be watered fairly often. However, appearances can be deceptive. The soil may still be quite cool, which means it will retain moisture for longer than you think. It’s important to test how damp it is before watering. Burrow your finger down into the soil. If it feels damp, don't water.
At this time of the year, if the lawn is too moist, it may be susceptible to fungal diseases such as fairy rings, moulds and dollar spot. If you suspect infection, apply a lawn fungicide according to label instructions.
Mowing the lawn
Early to mid spring is a great time to get your mower serviced and prepared for the workload ahead. If it’s a 4 stroke, change the oil, check the condition of the spark plug, air filter and the blades. Two stroke mowers should also have the spark plug and air filter checked.
If the blades are very worn, they should be replaced. Otherwise, clean them up and sharpen them with a wet stone or fine file. The spring lawn may be soft and lush and if the mower’s not serviced, it may not be up to the task at hand and could even rip your lawn up.
If you’ve been mowing with a catcher over winter, change to mulch mowing now and put the catcher in the shed.
See more tips on mowing in our Complete Guide to Lawn Care.
As the grass puts on a surge of growth in early to mid spring, weeds can do the same. Feeding the lawn to thicken it up will help keep weeds at bay. Very sparse areas are the most likely to become infested with weeds but even the best kept lawn can fall victim to a wind-blown seed.
Before weeds get a stranglehold, you could use Scotts Lawn Builder + WeedKill (Slow Release Granular Fertiliser + WeedKill instead of All Purpose Slow Release Fertiliser) for the first fertiliser application.
Check your lawn type is suitable because some weed and feed products are not suitable for buffalo and other wide blade grasses. On these grasses, use Lawn Builder Buffalo as the base fertiliser, then follow up with an application of Lawn Builder Bindii, Clover & Broadleaf hose on to eradicate the weeds.
ALWAYS read the labels to ensure products are suitable for your lawn type.
Moss in shady lawn areas
Over winter, when soils are often damp and cold, mosses can become troublesome in lawn areas that are shaded for most of the day. Spring is the time to control moss in shady areas with a solution of iron sulfate (30 grams in 4.5L of water) applied as a spray or with the watering can will help control it. Re-apply if necessary in a couple of weeks.
Repairing and patching the lawn
Bare patches can be oversown with a lawn seed blend around mid spring. Don’t sow too early because the seeds need warmth to germinate and grow away. Choose a seed mix that will match or complement your existing lawn. Break up the soil crust on bare spots by raking, sow the seeds and keep moist until they sprout.
There’s more information on lawn repair in our guide to fixing thinning and bare patches.