Landscaping Healthy Lawn Grass
A healthy well cared for green lawn is an attraction and therefore an asset to any property be it large, small, residential, industrial, sports field or park but a neglected lawn is of no value or attraction to anyone. There are three main types of lawn grasses which are used by home gardeners and landscape professionals in the garden, parks or sports fields of South Africa and each one of them have their uses and specific characteristics. Some types of lawn grasses withstand heavy traffic where they are used on sports fields while others are better suited to shady, sunny, small or large gardens and lastly there are those which will grow in poor soils.
Common Lawn Grass Varieties
KIKUYU A fast growing very vigorous
grass which needs good soil, plenty of fertilising and water.
Kikuyu must preferably be planted in sunny positions, although one
sees it growing in light shade. It can be invasive to flower
beds and paved or tarred areas. It is not the waterwise choice.
BUFFALO (Stenotaphrum secondatum) A slower growing grass, flatter in habit with deep green-grey blades. This grass will grow in either full sun or part shade. The soil can be light, heavy, damp or dry because it does not require much fertilising, cutting or watering.
BERMUDA (Cynodon Dactylon) A vigorous, fast growing grass best suited for sunny positions and light sandy soils, although it can be grown on heavier textured soils. This Fine-quick or Cynodon grass grows vigorously in summer when the weather is warmer. The growth rate slows in winter. The Fine-Quick grass type does not need as much feeding, watering or cutting as Kikuyu requires unless one is using it or one of the other varieties of Cynodons for golf tees, putting greens and bowling greens. It will look better if it is fertilised and watered.
LM BEREA (Dactylocenium australe) This grass is more shade tolerant than Buffalo grass and is the recomended choice if you need to grow a lawn in a shady area. It has the added advantage of having a reasonably similar leaf shape and size to Buffalo so it can be planted in the shadier areas were your Buffalo lawn is becoming sparse and the two grass types will knit together with little variance in appearance except for the lighter leaf colour of the LM Berea grass. Remember to set your lawn mower to the maximum height setting when cutting grass in the shadier areas of your lawn. The lawn needs extra leaf area to absorb enough light to grow successfully.
Here are a few basic steps which one should follow when planting a new lawn:
- Dig over the area to be planted to a depth of approximately 30cm (12") and remove any rubble, rocks or rubbish that you encounter.
- Spread a generous amount of compost together with approximately 150 grams of HOOF & HORNMEAL, KELPAC soil conditioner as per the manufacturer's instructions and 100 grams of superphosphate over each one square metre of soil. The former mentioned organic fertilisers will not burn the newly planted grass, albeit in sod, plug, runner, or seed form and will improve the soil texture and therefore the growth of the new grass.
- After applying the compost and fertiliser dig over the area with a garden fork to a depth of 5 to 7cm, level the area off and then finally moisten.
Planting Your Lawn Grass
Depending upon the variety of grass chosen one may either plant
from runners, sods, from mat form (similar to carpet tiles), from
rooted plugs in the case of Buffalo grass or from seed, as in the
case of Shade-over or Shadi-lawn.
Always plant or sow in damp soil, firming the soil as you plant or sow or in the case of sod, lay them close together on damp level soil and when completely laid cover over with a lawn dressing or suitable soil so that the newly laid mats are protected from drying out especially if planting in summer.
Keep your newly planted grass seed, plugs or runners damp by watering each day for the first week (water twice a day if the weather is hot and dry) then every second day during the second week, and then about every third day during the third week. Increase the amount of water applied in each watering session as the frequency of the watering decreases.
Grass sods should be kept well watered for the first week and thereafter twice per week for the second week and then once per week thereafter.
Watering Your Lawn Grass
It is essential that newly planted grass be kept damp so that the new roots readily become established. Should you allow the soil surface to dry out for a day or two, the new grass or grass seed may shrivel and die.
However, established lawns should be watered deeply but less frequently and not watered lightly every day or every second day as is often the case where automatic watering systems are used. It is better to water once per week to a depth of 30mm per application than to give two or three millimetres every day. Frequent light watering wastes water due to excessive evaporation and frequent heavy watering leaches nutrients out of your soil.
25mm of rain will penetrate 30mm into sandy soil, about 20mm into loamy soil and about 10 to 12mm into clay, therefore, if a lawn is to be watered to a depth of 30mm once per week it would need 25mm of water if planted in sandy soil, about 40mm of water if planted in loamy soil and about 70mm in clay. It is worth noting that you can save substantial amounts of water by improving clay soil with compost.
Test the "rainfall" from the sprinkler by using a simple scheme.
Place a number of coffee cans or plastic bowls, spaced at regular intervals in a line running from the sprinkler. Measure how long it takes to fill those jars to the average depth that your particular soil type requires and then you will know how long you will need to leave your sprinkler watering the area in question.
Fertilising a Lawn
To keep a lawn looking neat and attractive it must be regularly
cut, fertilised and watered. The more fertiliser and water you
apply the faster the grass will grow and the more that you will
have to cut. Fertilisers that have a high N number contain a high
quantity of nitrogen and it is this part that stimulates growth and
makes the grass go a deep green colour. Fast growing grasses such
as Kikuyu, growing in light textured soils will need more
fertilising than a heavier textured soil. Lawn grasses such as
Kikuyu and Fine-Quick should be fertilised about every two months
from the first week September until the last week of April using a
fertiliser that is suited to your grass and soil type.
Slow growing grasses such as Buffalo and Wonder-Lawn can be given light applications about every three months depending upon soil texture and type.
Spray Ammonium Sulphate or Limestone Ammonium Sulphate on lawn areas that have been neglected using a Mix Nozzle and it will work wonders for the condition of your lawn but this should only be used as a quick improver and not for long lasting results.
Grass should be allowed to grow relatively thick in summer because this helps to keep the soil cool and therefore more moist and so requires less water. The grass mat can be progressively cut shorter in the Autumn (late March and early April) so as to get a relatively short firm lawn by the end of May. This allows light, air and moisture to penetrate the mat of the lawn. Rotting and disease can occur in the undergrowth if the grass mat is kept thick in winter but be careful not to cut "Shade-Over" type grass short because it will die off, particularly in the deeper shade areas.
Weeds can be kept under control either by using a two-pronged fork to remove occasional largish weeds or by using a selective herbicide but always check to see which herbicide can be used to control your problem. Regular mowing makes it difficult for many weed types to establish themselves in your lawn.
Top Dressing a Lawn
Sometimes a lawn needs to be levelled or top-dressed but it does not follow that it is an absolutely essential part of having an attractive lawn. Light dressings of good quality compost or a mixture of compost and river sand applied after you have either cut or fertilised your lawn will work wonders. Do not top dress in the middle of winter when the growth is at its slowest but rather start in spring and continue as and when necessary right through late April. Any severe depressions should be filled in by first lifting the sod, filling in the depression with good soil and then replanting the sod.
Lawn Grass Disease Control
Pests and fungi attack any type of plant. Grass, roses,
vegetables, shrubs, fruit trees, etc. have their share of insects
and fungi which attack them from time to time.
KIKUYU grass, is very prone to three fungal diseases:
- "BROWN PATCH"- Identified by circular patches which go brown and then dry out.
- "DOLLAR SPOT"- Small bright brown spots about 50mm in diameter.
- "RUST and LEAFSPOT"- Purplish spots in the blades of the grass.
Fungal diseases are normally found to occur in lawns that are hungry, where the soil is compacted, where the grass might be growing in the shade (Kikuyu or Fine Quick) and most important of all, if excessive use has been made of high nitrogen fertilisers. These fertilisers promote soft growth which is more prone to rotting disease. Another contributing factor is where lawns have been watered at night which helps fungus to get established and spread quickly. Early morning watering is best (do not water too early on winter days in frost prone regions).
To combat these diseases make sure your grass is regularly fertilised and preferably fertilised with organic fertiliser or a chemical fertiliser that is high in potassium such as 2.3.4. Water as per the instructions above. Finally spray the affected area with either Copper Oxychloride or Permanganate of Potash. Repeat at 10 day intervals for five applications until all traces are eliminated.
Generally speaking, experience shows that it is better to be pro-active in controlling lawn pests and diseases. As an example, if the lawn has already been attacked to an excessive degree by either pests or diseases, then it is better to resort to a quick acting contact pesticide or herbicide, than to use a slower acting systemic one (as the lawn may be completely devastated by the time the substance takes effect). Rather address the problem at an early stage than wait until it is difficult or impossible to contain - the choice is essentially yours, but in the latter case you will probably have to resort to a contact pesticide or herbicide. Currently there are excellent products on the market for combating pests and diseases.
These can be a problem in mid-summer. Check for caterpillars in
the drying and yellow areas of your lawn by applying a heavy
drenching of water mixed with a little soap. If they are there they
will soon rise out of the grass. Another method is to place a wet
sack on the grass and leave it there overnight. When you lift the
sack the next morning the caterpillars will be visible and possibly
even a small white conical snail.
To control these pests water the infected area with Dipterex or Karba- Spray or blanket the lawn area with organic tobacco dust.
Mowing Your Lawn
It is not recommended to cut grass short in the summer months in
the Western Cape due to the hot, dry and windy conditions which
prevail in the area. Rather keep your lawn about 50mm thick
(or high). In late March or early April start to cut it shorter so
that in winter you have a short firm surface.
Collection and reuse of grass cuttings is favoured by some gardeners but not by others. Grass cuttings can make a good source of mulch or compost if handled in the correct way. One could leave some of the cuttings on the lawn if the lawn area is large to create a mulch which would subsequently become a source of food but do not leave too thick a layer behind on the lawn because this could lead to rotting and subsequently to fungal disease spread. Collect the cuttings if the lawn area is small and place them around the shrubs in your garden so that they form a thin mulch which will later decompose and become a source of nutrients.