New Lawns from Seed
If you managed to dig over the lawn seed bed in the autumn it should now be ready for its final preparation. The winter frosts will have broken down the soil, making it easy to produce a good tilth. If, however, you have been unable to give the ground an autumn digging, thoroughly dig the site over on a fine dry day. Turn old rough grass face downwards and remove the roots of perennial weeds such as bindweed and couch grass.
Rake the seed bed several times in different directions to produce a fine tilth and level surface. This will also remove many stones and kill annual weeds. Thoroughly tread the soil to consolidate the ground and produce a firm, even surface.
Some weed seeds may germinate after the seed bed has been prepared but before the seed is sown. These can most safely be cleared by watering with Paraquat based weed killer such as Weedol.
To aid establishment of the new seedlings apply a pre-seeding fertiliser evenly over the seed bed area and lightly rake it into the surface. A suitable pre-seeding mixture is: sulphate of ammonia 2 parts, superphosphate 4 parts, bonemeal 4 parts, sulphate of potash 1 part.
Apply the fertiliser evenly at 3 oz. per sq. yd. and rake it into the top inch or so of the soil surface.
Beware using any sort or organic matter based fertiliser. This will cause uneven settlement in the lawn as this organic matter is broken down during the rotting process.
When selecting a seed mixture, consider the amount of wear anticipated, the degree of shade and the cost of the seed. Most mixtures consist of three or four species, usually blends of tufted and creeping grasses, which will grow well together and mature at different seasons. Ryegrass mixtures, which are the cheapest, are suitable only for lawns subject to heavy wear and tear, where appearance is a secondary consideration. Crested dogstail should be included in the mixture if a hard-wearing lawn of fine quality is required. A number of leading seed firms supply balanced mixtures for both general and special purposes.
About a week after applying the fertiliser, sow the seed at 1-2 oz. per sq. yd. after making a final check that the seed bed is level and free from stones, and has a good fine tilth. Consider delaying sowing until the weather is beginning to warm up possibly towards the end of the month. Broadcast the seed, distributing half in one direction and the remainder at right angles. Lightly rake the surface to cover the seed.
The seed will germinate in about 14 days. If it has been already dressed with a bird repellent, little trouble may be expected from birds, but keep a careful watch for symptoms of damping-off. It may be recognised by the appearance of brightly coloured red and purple patches of collapsed grass. The disease is difficult to control, but the following treatment will help to check its spread and will encourage the grass. Water with Cheshunt compound using 1 oz. to 1/2 gall. water per sq. yd. Follow with an application of ammonium phosphate at 1/4 - 1/2 oz. mixed with 3 1/2 oz of sand per sq. yd.
When the grass is about 3 in. high, give the first light mowing. This will firm the seedlings in the ground, but if there is any tendency to pull the seedlings out the ground may be too wet or the mower not sharp enough.
Check the sharpness and adjustment of the mower by placing a piece of news paper between the cutting cylinder any the sole plate. If the paper is cut easily the mower is sharp enough and correctly adjusted. Use a side-wheel mower for preference and remove only the to 1/2 in of leaf. This encourages tillering (branching from the base of the grass) thereby ensuring that it spreads over the soil surface.
Generally a rotary mower with a roller is ideal for the first or second cut. Surprisingly, don't collect the grass clippings with these cuts, but allow them to fall back into the young sward! A little thatch will also help the resilience of the new lawn.