No matter how much effort you put into your flower beds and landscaping, your garden won’t look good if the grass is patchy and weed infested. We asked Richard Erasmus of Lawnpro, a professional with over two decades’ experience in residential lawn care, to answer some common questions about creating and maintaining a lush lawn
WHICH TYPE OF GRASS SHOULD I CHOOSE?
Consider your climate, the amount of sunlight the lawn will receive, how much traffic the lawn will take and how easy it is to establish. Your options include warm season grasses and cool season grasses.
Kikuyu is the most popular of the warm season grasses, followed by LM lawn, buffalo lawn and cynodon – these grow best in sunny areas, are more tolerant of traffic and are easy to establish and maintain. LM and buffalo grass can also handle less sunlight and will do better than even the strongest kikuyu lawn in a 30 percent sun-filtered environment.
Cool season grasses include evergreen mixes such as All Seasons Evergreen, Starke Ayres Evergreen Mix and Lawnpro Green Domein, shade mixes like Shade-Over, Starke Ayres Shady Mix and Lawnpro Under Cover and various over-seeding rye grasses. For a green lawn all year round in the coldest climate, or a green lawn in shady areas, this is the route to go. However, they don’t tolerate a lot of traffic, require more frequent watering, take more time to establish and may need constant seeding and nurturing.
HOW OFTEN SHOULD I WATER MY LAWN?
- You need to water your lawn to supply the right amount of moisture, cool down the soil temperature and wash fertilisers into the soil. As clay soils hold moisture for longer than sandy soils, you’ll need to water grass planted in sandy soils more frequently. However, clay may hold onto water more intensely, preventing your lawn from utilising that high moisture content. Loam is the ideal soil mix and will retain just the right amount of water, while still releasing enough moisture.
- If you have loamy soil with a warm season grass, give your lawn a good soaking of water once a week, and perhaps just cool it off if the grass is under stress from extreme heat. The norm is 25mm of water per week. Place a container in each of the sprinkler zones and determine how long it takes to fill the container up to 25mm; this is the amount of time you’ll have to irrigate each zone once a week. It’s better to give more water in one session to force the roots to grow down to a deeper level, than giving a little water every day.
- Cool season lawns need more frequent, shallower watering, as their root systems are not as deep as some of the warm season lawns.
- Water early in the morning as this is the coolest time of the day and there will be less evaporation. You’ll lessen the chances of your lawn contracting a disease if it dries before nightfall.
- Water spots where pets have urinated immediately, or at least more frequently, using a watering can or hose.
*Tip! An easy way to tell if your lawn needs water is to walk on it. A healthy lawn feels soft under your feet. If the lawn feels crusty and it breaks when you rub your hands over the top of it, it’s not getting enough water.
HOW OFTEN SHOULD I MOW, AND AT WHAT HEIGHT?
Mowing is one of the greatest ways to bring out the best in virtually any lawn. If a lawn grows really fast and there is a lot of leaf development and growth then you may have to mow your lawn more than once a week.
The biggest mistake made in lawn care is cutting the lawn too short – it’s important never to cut off more than 1/3 of the leaf blade in one go and also to keep mower blades sharp.
Keep kikuyu at a height of 4–6cm above ground, finer grasses such as cynodon, at a height of 3–4cm, and LM lawn and cool season lawns at a height of 5–7cm. This results in deeper roots which are more capable of surviving dry spells.
WHAT IS SCARIFYING AND AERATING?
These two practices involve removing dead root material from a lawn and ventilating the root system in the growing season when the underlying thatch becomes a visible problem.
Aeration is carried out to enable air to get to the roots. It aids drainage and also allows water, minerals and nutrients to reach the roots. It’s done by using a spike roller, fork or a hollow tining machine to punch holes into the soil.
Scarifying is a process where a rotary-type mower is used to cut into the soil. Bolts or pins are fitted to the rotary blade and the mower is then set to its lowest setting. This is followed with an application of fertiliser and lawn booster.
Scarifying puts the lawn under stress as it is torn rather than cut, which can make it susceptible to disease and there is the possibility of cutting the live root system. An alternative is to get a professional to dethatch or verti-cut your lawn, that is to remove the zone of dead grass roots that builds up below the soil surface. This process rips into the grass vertically, tearing into the roots and cutting them vertically, leaving a lot of roots intact to immediately start growing.
HOW DO I DEAL WITH WEEDS, PESTS AND DISEASES?
Weeds: Most weeds are broad-leafed and are quite simple to get rid of using the correct selective weed killer (herbicide) for broad-leafed plants. Always follow the instructions on the label exactly; this is not a case of ‘the more you apply, the more they die’. Avoid mowing your lawn before you apply the herbicide and allow 24 hours to pass after applying it before watering or mowing your grass.
Insects: Carry out a pest control regime on a regular basis so that destructive insects don’t reach a point where they destroy your lawn completely. Change the insecticide frequently to prevent pests from building up a resistance to any one type; use organic products whenever possible.
Lawn diseases: The difficult aspect of disease control is identifying the specific disease; it’s often best to ask your local nurseryman for advice. Some diseases may require you to apply fertilisers, while others will thrive on even the smallest amount of nitrogen in a fertiliser application. If a disease is noticed on a lawn, aerate the soil as soon as possible as most diseases flourish in areas with poor drainage, heavy traffic and poor soil fertility.
WHAT IS TOP DRESSING (LAWN DRESSING) AND WHEN AND HOW SHOULD IT BE APPLIED?
Top dressing is a mixture of well-balanced organic matter and weed-free soil. A thin layer should be spread on established lawns between August and February, if necessary. It’s applied to level an uneven surface or help a lawn recover after a serious disease or a very cold winter by replenishing nutrients.
Buffalo grass, LM and all cool season lawns don’t tolerate lawn dressing at all. If the lawn needs to be levelled, remove the areas of uneven grass carefully, level the soil and replace the old lawn.
The amount of top dressing you use depends on your lawn type, but as a rule of thumb, the recommendation is to cover 100m² of lawn with 1m³ of sterilised lawn dressing.
HOW OFTEN DO I NEED TO FERTILISE AND WHAT SHOULD I USE?
A good general fertiliser for all lawn types is 5:1:5 (36). These numbers indicate the amount of nitrogen (5), balanced phosphorus (1) and potassium (5) it contains. The (36) indicates the percentage of these three elements in the mix. Apply this fertiliser during the growing season at a rate of 60g/m² at least once every three months.
You can feed your lawn during winter using a fertiliser, like 2:3:2, which contains less nitrogen and more phosphorus; as most warm season lawns become dormant in the winter, they do not need high volumes of nitrogen.