Creating A Green Lawn In A Hot Climate
Creating a lawn for seed and turf, the preparation should be the same to achieve the best results.
You will need to kill all the existing grass plants and/or weeds in the new lawn area. You can either remove the weeds by hand, i.e. digging them up, or you can use a weed killer such as Glphosphate; trade name Tumbleweed or Round-Up. We don’t often recommend chemical weed killers, but in the case of lawns, using a small amount at the beginning can save a whole load of chemicals being used later, to control existing weeds established before the lawn was created.
Ideally, you should leave the ground for a couple of weeks to see if any further weeds try to establish themselves. It is worth noting that when using Glphosphate the longer it is left before cultivation, the further back down the tap root and creeping stems it will travel.
With the existing weeds taken care of the next stage is to move the soil around until you achieve the basic levels you require. This can be achieved in the case of a level or uniformed sloping lawn with pegs and a straight piece of wood. Simply start with the first peg hammered into the ground to the required level. Use the straight piece of wood and a spirit level to establish the next peg at the same height. For a larger area, you can hire a small building level from your local hire centre.
Whilst starting to level the area, it is a good time to add some organic matter by spreading it onto the surface. Often in hot climates, the soil has little or no organic matter, it is the key to deep rooting of the grass plants that helps the lawn maintain a good colour in hot weather. The organic matter can take the form of well-rotted farmyard manure, horse manure, spent hops or crushed grapes from wine production.
At this stage, you should have achieved a roughly level area and have spread some organic matter on the surface. To this, add a dressing of a phosphate-based fertilizer such as Super Phosphate; you will require 25 grams to the square metre. Then add an application of a product called Water Save; about 10 grams per square metre. This is a crystal-type chemical that helps grass plants access the water in the soil.
Next, you need to prepare the final seedbed. Fork over the soil to a depth of about 125mm, on larger areas you can rotovate. Then start to rake in several directions using a garden/landscape rake to remove all the stones over 12 mm. Ideally you are aiming to create a fine tilth with the organic matter etc mixed into the soil
As you work the soil it will become compact, but in addition to this, you need to tread the soil, which means walking over it with small steps on your heels or using a roller to pull over the area. As you carry out these operations you will be able to see or feel the high and low spots and using your rake adjust the levels accordingly.
It is worth using most of your available time on the preparation, as it makes all the difference to the quality of the lawn in the long run.
The seedbed should now be created to the required levels and reasonably fine tilth on average soil lumps about 3 to 4 mm. If you have problems breaking down the soil to this degree then try watering it and leaving it for 24 hours, as often this can help.
Concerning stones, if you still have small stones on the surface do not worry, these will be removed later. If your soil is very stony the solution is to import some additional soil, which is free of stone, and lay it over the surface to create a layer of about 20mm. The problem you might encounter with importing soil is that you import weeds as well.
You need to seed the area with a very fine seed mixture with additional fescue grasses, as this type of mixture will hold the colour in the summer. The seed packets will show you the percentages of different types of seeds in the mixtures. Try to stay away from a mixture with species and regress because although it will establish quickly it is not going to last in the hot summers.
To seed, the area evenly spread about 25 grams per square metre and lightly rake in, then roll this is key in helping the seed make good contact with the soil so that it might take up the soil moisture to help germination.
Once the seed is sown you need to keep the seed bed moist at all times. If the weather turns very hot it is worth covering the area with horticultural fleece to shade it from the sun.
Concerning birds, as long as you have raked the seed in and rolled the area, the amount suggested allows for birds to take about 10 per cent of the total.
Finally, the addition of Root Grow Plus from www.friendlyfungi.co.uk will help. This is a mixture of Mycorrhizal fungi constituents which team up with the grass plants and helps them become efficient at accessing water and nutrients from the soil. At present, it is still expensive to use with lawns as it is a new product, however, it is worth the extra expense.
To use, take a small stick, make 2 holes in every square metre of seedbed about 25 mm deep and add a few granules into the hole.
With watering or rain, once the seed is about 25mm high, you will find that new stones have been exposed. Lightly rake the surface with a wire rake the type used for removing autumn leaves and remove any larger stones by hand. If you are also pulling out the grass plants then leave this operation for a further 7 days. With the stones removed you now need to roll the area with a garden roller, slowly, in two directions to help the grass plants produce additional leaves and fill out to start to form your lawn.
In a hot climate, irrigation is going to be key. It is ideal if you create underground water storage tanks, we often use septic tanks, to collect and store the winter rainwater or create a pond to hold the water.
The key in hot climates is to irrigate the lawn only once every 8 days but to completely flood it with water so that the water soaks into the depths and does not get evaporated by the sun. If you have prepared the soil correctly the water will penetrate the soil quickly.
To summarize, here are the steps to prepare a new lawn area for seed or turf:
- Kill existing weeds or grass plants in the new lawn area by hand or with a weed killer like glyphosate.
- Level the soil and add organic matter, such as well-rotted manure, to the surface.
- Apply a phosphate-based fertilizer like superphosphate (25 grams per square meter) and a water-saving product like Water Save (10 grams per square meter).
- Prepare the final seedbed by forking the soil to a depth of about 125mm and raking to remove stones larger than 12mm. Tread the soil or use a roller to create a fine tilth.
- If the soil is very stony, import additional soil that is free of stones and lay it over the surface in a layer of about 20mm.
- Seed the area with a fine seed mixture that includes fescue grasses, aiming for about 25 grams per square meter. Rake and roll the seed to help it make good contact with the soil.
- Water the seedbed regularly to keep it moist and prevent the seeds from drying out.
- Once the grass has grown to a height of about 50mm, it can be mowed for the first time.
Remember, proper preparation is key to achieving a healthy and attractive lawn. Take the time to prepare the soil properly and follow the steps outlined above to give your new lawn the best chance of success.
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