Spring Laen Mow Thumb

Spring is one of the busiest and best 'windows of opportunity' in the garden. Now's the time to fix any problems with your lawn, so it's healthy, green and ready for maximum summer enjoyment. Here's what to look out for, and lawn tasks to tackle.


Beginner Intermediate Advanced
Weekend

Is It Time for a Lawn Reno?

Lawns can struggle through the winter period, as they can't grow fast enough to deal with the damage caused by regular foot traffic, active kids and pets, or cold wet weather. If your lawn has taken a battering, spring is the ideal time to restore it with some renovation 'TLC'.

De-Thatching

De-thatching established lawns is best carried out from mid-spring to early summer, so the weather is warm enough to promote fresh new grass growth. Lawn thatch is the layer of organic material that forms under your grass, on top of the soil. Thatch formation can be accelerated if the soil is low in microbial life, which means soil microbes can't break down dead thatch material fast enough to keep up.  A small amount of thatch is beneficial, as it helps prevent evaporation, aids water retention and can increase tolerance to wear and tear. However, too much thatch can prevent water, fertiliser and air getting down to the soil and grass roots.

Thatch needs to be removed by a process called ‘de-thatching’ or scarifying. This can be done by mowing the lawn at a low level (this can be completed over several mows, lowering the mower at each cut) or very vigorously raking the lawn with a strong rake (sometimes called a thatching rake). Lawn scarifier machines are also available from hire merchants.

Apply a gentle lawn fertiliser and water well after de-thatching. This helps water penetrate down to the root zone and kickstarts healthy grass growth. The rich organic ingredients in Yates Dynamic Lifter Organic Lawn Food will give your soil ecosystem a welcome boost; in turn, this boosts grass nutrition and helps improve drainage and soil porosity.

Aerating Soil Really Helps

It's difficult for air, water and nutrients to penetrate into hard compacted soil. This makes it much harder for both microbes and grass to grow and flourish, so it’s a good idea to amend and improve areas of compacted soil by aerating it. Aeration is one of the keys to having a beautiful lawn. Aerating removes small plugs of soil, helping to open up the soil and improve water, air and nutrient penetration down into the root zone.

Aeration can be completed using a mechanical or inexpensive hand corer, with a foot bar so you can use your weight to push it down by standing on it. Hand corers are great for small, lightly compacted areas, but it's hard work! For areas that are large or heavily compacted, we'd recommend hiring a mechanical corer, or just get in a contractor to do the job. Cores should be made every 2.5cm X 5cm, across the whole lawn.

Mow the area down low and water the day before to soften the soil. Aim to create 5cm-7.5cm deep cores in the compacted soil, approximately 2.5cm apart.

Topdressing

After you've aerated your lawn, it's highly recommended to topdress with fine 80/20 mix (80% sand, 20% loam) over the whole lawn, at a rate of 1m3 of lawn mix per 10m2. If you lightly rake the dry mix into the core holes, your lawn will love it.

Topdressing is also beneficial if the lawn is a bit bumpy or uneven, or has tracks worn into it by pets or kids playing. To level out any low areas, begin by mowing the grass down low, then top dress the area with 80/20 sand and loam mix to bring the low spots up to the level you want. It's best to spread only 1-2cm in depth at a time to level out the area, and then water well. Be sure your topdressing mix has a fine texture, to ensure it filters down to allow new leaves to poke through. Following up with an application of Yates Dynamic Lifter Organic Lawn Food will quickly encourage new blades of grass to peep up through the layer of topdressing.

Fix Scruffy Lawns by Over-Sowing

Early spring is an excellent time to fix damaged, thin or patchy lawns, because it gives grass seedlings time to establish before the hot weather arrives and puts them under stress.

Bare patches in the lawn are a magnet for weeds to establish and spoil the look of the lawn. Also, it's common for established lawns to become thin and worn over time and they can benefit from over-sowing with new lawn seed to help thicken up and revive them.

For bare patches, first remove any weeds or dead grass from the patch. Gently cultivate the soil in the bare patch with a rake or garden fork to create a soft, loose surface. You can also spread some handfuls of lawn mix over the patch. For thin lawns, applying some lawn mix over the entire area can help improve new lawn seed establishment by providing a softer and loose surface. Yates Seed'n'Feed is ideal for oversowing bare patches.

Alternatively, mix the required amount of lawn seed with a turf starter fertiliser, like Yates Lawn Fertiliser for New Lawns. This clever fertiliser is gentle enough not to interfere with seed germination, or burn delicate baby grass; plus it contains a rich blend of slow-release nutrients to gently kickstart your lawn. Mixing seed and fertiliser makes it a quicker job to cover bare patches or over-sow existing lawn, plus it adds valuable organic matter to the soil and provides the new grass seedlings with gentle slow release nutrients as they establish. If you've already sown your lawn seed, it's no problem; you can still apply Yates Lawn Fertiliser for New Lawns at any time after sowing.

Scatter the lawn seed, either by hand or with a spreader, then gently rake the seed into the soil surface. Keep the patch or area moist for several weeks while the new grass establishes.

Try to minimise foot and pet traffic on the newly sowed area until it's well established.

It's a great idea to improvise some bird scaring devices while your tempting, tasty grass seed is germinating. Old CDs strung onto bamboo stakes work well. Christmas tinsel and brightly coloured ribbons fluttering over your sown area really help to keep bird losses under control. Or best of all, ask the kids to create you a scarecrow that flaps in the breeze and makes noises; then prepare to be amazed!

Watering Baby Grass is Crucial

Water thoroughly and regularly for a few weeks until the grass is established. During the first few days of germination, make sure you don't let the seed dry out, at all. Allowing the soil to dry out even for a short time can halt germination and kill delicate embryonic grass. It's likely you'll need to water multiple times a day during the first few days, then continue to keep a close eye on the moisture after that.

Feeding

Grass needs a readily available fertiliser during late winter or early spring to wake it up for the key growing season. A healthy lawn won't need feeding again until late spring, but if your lawn started the season off in poor condition, a second application can be made 8 weeks after the first. 

Yates Dynamic Lifter Organic Lawn Food, which combines composted chicken manure, blood & bone, fish and seaweed is ideal to enrich the structure of the soil. It does this by adding organic content that encourages earthworms and beneficial soil micro-organisms, that in turn help to improve the soils porosity (drainage) and air movement. This all makes it easier for your lawn to grow and root deeper into the soil.

In spring, there are real advantages to using a premium slow-release fertiliser. Reduced frequency of application is an obvious one, but avoiding surges or spikes in growth and nutrient overload is also a major benefit. Slow-release fertilisers perform consistently well throughout the year, because they supply just enough nutrients to match the grass’s needs, whether it’s dormant or growing flat-out. They tend to be more expensive than standard granular fertilisers, but we think the benefits make this type of fertiliser the best value for money.

Keeping your soil microbes happy is the secret to a good lawn, because the microbes break down fertiliser into a form that lawn grass can absorb! When you feed your lawn, you’re actually feeding the soil microbes: they respond by feeding the grass for you. Your lawn grass and microbial soil community underneath it are in sync with each other, and with the seasons - when the grass becomes dormant, the microbes are also snoozing. As soil temperature rises and everything begins to speed up, grass nutrition is able to accelerate, because most of the nitrogen in slow-release fertilisers is actually 'unlocked' for grass by soil microbes. 

For controlled release lawn foods, this means that nutrients are only supplied at the rate grass can use them; in comparison, the excess nutrients in fast-release fertilisers can go to waste at cooler times of the year. If you feed your lawn a big dump of fast-release nitrogen in cold conditions, it won't be completely absorbed - the excess nitrates can remain in the soil and will eventually leach into groundwater.

Yates Lawn Fertiliser Twice A Year is a premium controlled release granular fertiliser, suitable for all New Zealand lawn types: including kikuyu, ryegrass and fescue. It gradually releases nutrients for up to 6 months, so you achieve a long-lasting consistent result, without surge growth.

Yates Lawn Fertiliser Quarterly is a clever granular lawn food that combines the benefits of both fast-acting and gradually released nitrogen: the fast release component provides rapid results in 7 days, while the slow release feeds over a prolonged 12 week period.

You'll get the best results from applying fertiliser regularly, at the intervals suggested on the label. Don’t wait until the lawn starts to look hungry, because reviving a nutrient-depleted lawn always takes more time (and $) than sticking to a regular fertilising schedule does. The fertilising rule of thumb is ‘light and frequent’, for best results.

Weeding

It's important to control broadleaf weeds, because they'll compete with your new grass. Luckily, it’s pretty simple to control lawn weeds with a selective herbicide. This is the type of weedkiller that removes weedy invaders without harming your lawn grass.

The simplest way to get rid of weeds like dandelion, clover, capeweed and thistles in your lawn is with Yates Weed n Feed Double Action Hose On. It's ideal for cool-season grass types like fescue, tall fescue, perennial ryegrass and bent/browntop.

A word of warning though, if you're oversowing grass seed it pays to time your weedkiller applications carefully. Selective lawn weedkillers can affect the germination rate of grass seed, if you sow too soon after you've applied weedkiller. The rule of thumb is to wait for 4-5 weeks after using lawn weedkiller, before you sow grass seed onto the treated area; this ensures you get peak grass germination and excellent results from your hard work.

If you aren't oversowing, the job is much more straightforward. If you didn't get onto the weeds back in autumn, it's not too late, but make sure you move fast! Many weeds will be starting to flower and set seed; these will happily germinate new weeds in your lawn next autumn. If you control them now before they have a chance to set seed, next season will be easier to manage.

Yates Turfix Lawn Weed Spray is our go-to choice if you don't mind using a sprayer or lawnboy. It's effective against a very wide range of lawn weeds, so an application in spring (and another in autumn) will give you excellent results.

Remember the kids complaining about prickles in their feet over summer? Your window of opportunity to control Onehunga weed before it flowers and forms prickles, closes in late spring. Yates Prickle Weedkiller is our go-to product for this nasty little weed.

You might also encounter one of the persistent offender lawn weeds that you'll need to call in the big guns for - native hydrocotyle and creeping oxalis are examples. To get on top of these difficult weeds, choose Yates Hydrocotyle Killer for the job.

Grass Grub and Porina Prevention

During the first half of spring, it’s quite common to encounter symptoms of a grass grub or porina infestation.

By the time spring arrives, grass grubs have been chewing steadily through the winter, causing increasing damage as they grow larger. Although the damage to the lawn is already done, it’s still an ideal time to ‘take care of them’ because the adults are flying and laying eggs in spring.

Grass grubs are the larval stage of the native grass grub beetle, which chews at the roots of plants and lawns. Larvae are most active from late summer until the end of winter, and can cause severe damage to lawns, gardens and potted plants. Early in spring they pupate, before emerging from the soil as adults from late spring until summer.

Adult beetles are attracted to light, it’s quite common during the second half of spring to see beetles buzzing around street lighting. If your outdoor lighting is close to your lawn area, consider turning it off during spring, or avoid using it for extended periods so it doesn't look like an airport runway for beetles.

The classic symptom of grass grub infestation is brown dead patches developing in the lawn, which can be easily lifted up or rolled like a carpet. If plants in your garden or pots are wilting despite being well watered, that’s also a sign grubs may be at work. These symptoms will begin to appear earlier in winter but will be at their most dramatic by the time spring arrives.

Porina caterpillars are the larvae of NZ native porina moths. The nocturnal adult moths fly in large waves in spring and autumn, laying thousands of eggs. Lawn damage in winter and spring is caused by the moth flight from the previous autumn. The spring moth flight’s caterpillar symptoms show up between autumn and early winter.

Porina caterpillars emerge from burrows in the soil and graze on your grass at night. They don't move far from their burrows, so their grazing leaves distinctive bare soil patches with pencil width holes in the centre. These caterpillars don't feed on roots like grass grubs, they nip off grass stems then drag the grass into their burrows to eat it.

The good news? We have a really effective solution for both of these destructive pests (it controls lots of other pests too). Yates Lawn Grub and Porina Kill + Protect delivers excellent preventative control against grubs and caterpillars. It continues to perform for some time, giving you up to 6 months protection.

Keeping your lawn strong and healthy really helps it to resist pest pressure. Give your lawn a weekly deep watering, mowing at a higher level and feeding it regularly with Yates Dynamic Lifter Organic Lawn Food.

Yates Insect Killer for Lawns is a great solution to control surface-dwelling lawn pests, like African black beetles or armyworm.

Mowing

When did you last sharpen your mower blade? If the answer is "last autumn", you get a pat on the back. If that's not your answer, well, it's time for a sharpen! Sharp mower blades make a cleaner cut and cause less stress to the grass, which helps it recover faster. Blunt blades rip and tear the grass. If you look closely at the cut end ends of fresh mown grass, and you can see tiny strings of fibre along the cut where it's frayed and damaged, it's time to sharpen your blades. 

If you've been leaving your lawn longer over the winter, don't cut it savagely short just because it's spring; this can stress the grass and hold back spring growth. For the first cut, don't cut more than a third off its length....just a slight trim is best. Wait until the soil warms up and grass is noticeably growing before you cut it. After that, cut as frequently as possible, but remove as little growth as possible during each mow.

For established lawns, cut cool season grasses (e.g. ryegrass, fine fescue, tall fescue or browntop) to between 3 and 10 cm, and cut warm season grasses (e.g. kikuyu or couch) shorter, to 2.5 cm high. Keeping the grass long allows for more photosynthesis to really get the lawn cranking, but during a very wet spring shorter is better, to discourage lawn diseases.

If you’re not sure what type of grass you have, it’s a likely bet that your lawn will be a cool season blend in NZ. Usually, warm season grasses are found in coastal areas, in the warmer parts of the country.


Related Products


More Lawn Tips & Advice

Spring lawn care tips

Spring is one of the busiest times in the garden. Here are a range of things to be on the lookout for with your lawn.

Resuscitate your lawn

Does your lawn look a bit sad? The reason might not be as obvious as you think: thatch build-up or soil compaction might be the culprits. Here's what to look out for and how to tackle it.

Why and how you should fertilise your lawn

Lawns are made up of many thousands of small, hungry plants, that all consume energy. Seasonal bursts of growth and regular mowing can deplete the lawn’s energy reserves, so here's how to top it up.