IMPROVING AN EXISTING LAWN
The worst problem may be that a lawn is in poor condition and the grass may have a high weed population, and/or bare patches, or the grass may be very rough. The natural grasses may have 'taken over', and the finer types, normally used in lawns, either suppressed or lost.
If a renovation programme is to be carried out this will fall under five main headings, i.e.
- Weed control.
- Top dressings other than fertilizers.
- Other methods of improvement.
I would first stress that there is no magic wand available for changing the quality of a lawn overnight or even in a short time. The colour of the grass can be changed fairly quickly, i.e. within ten days or so in spring or summer, by giving a top dressing of a nitrogenous fertilizer, but it is not possible to change the grass itself from a coarse-growing rye-grass type to fine-quality bowling-green type of lawn.
It is certainly possible to improve the appearance and the growth. One of the most satisfactory advisory jobs I ever did was concerning a large lawn area at a house in Sussex where growth and appearance was chronic, due to years of neglect. A few manurial experiments in yard-wide strips were tried, and the results were little short of fantastic, or should I say fabulous? Growth and colour were improved out of recognition. As the lawn had had no feeding for many years, whilst such treatment did not alter the grass itself, it altered its growth, its root formation and the general appearance of the lawn very considerably. In short, try feeding first, if faced with a similar problem.
1. Feeding Where a lawn is in poor condition, and it is known that little feeding has been done, give a dressing of general fertilizer in autumn. This can be a ready-mixed proprietary lawn fertilizer, or one can be made up as follows : 2 parts bone meal, i part sulphate of potash and part sulphate of ammonia, all parts by weight. This mixture should be applied at the rate of 3 oz. to the square yard, and distributed evenly. Mark off the lawn in yard-wide strips, and weigh off the required amount of fertilizer for the number of square yards in each strip.
2. Weed Control Where perennial weeds are the main problem the best results will be obtained by using a selective weed killer in spring when both weeds and grass are growing fairly freely. The selective weed killers used for this purpose have most and best effect when the weeds are in active growth. It is better still, I find, to top-dress the whole lawn area to be treated in early spring with a light dressing of a nitrogenous fertilizer like sulphate of ammonia at oz. to the square yard, preferably in showering weather, then follow with the weed killer ten to fourteen days later.
Two applications of weed killer at ten-day intervals are better than just one application, especially when there are many weeds to deal with. Always follow maker's directions closely as to dilution, i.e. strength of solution.
The question can arise here—Is there an alternative to selective weed killers, and what about Lawn Sand?
The answer is that Lawn Sand is best used on broad-leaved weeds like plantains and dandelions, also daisies. It is made up of 3 parts sulphate of ammonia, 1 part sulphate of iron, 20 parts dry fine sand, and is normally applied at the rate of 4 oz. to the square yard. It can be purchased, ready to use, from garden sundries shops.
It should be put on in fine dry weather for best results. The immediate effect is to blacken the lawn, but this will lessen after a few days and then disappear. The effect is to scorch weeds, especially the broad-leaved types mentioned above. The nitrogen contained in the sulphate of ammonia acts as a stimulant to grass growth and gives a darker green appearance seven to ten days after treatment.
3. Top Dressings other than Fertilizers A dressing of peat is of benefit on a light sandy soil, and this should be scattered evenly on the surface in autumn. The type of peat used is the fine grade and can be purchased from most garden sundries shops.
Re-sowing Bare patches or thin places can be re-sown in early autumn or in spring, but it is important to rake or fork the areas concerned in order to get 1-2 in. of loose fine soil in which the freshly sown seed can establish itself.
This treatment is best associated with spiking in autumn (see later in this chapter) and the peat brushed into the spike holes. Better (grass) root development will result from the joint effect of the aeration and the peat dressing.
Re-sown patches can stand out, being perhaps of different texture from the remainder of the lawn, but any marked contrast will lessen after a season or two.
It is possible to re-sow in summer, but water the re-sown area if the weather is warm and dry, and cover with a thin layer of grass mowings.
5. Other methods of improvement
Spiking Aeration can be done by using an ordinary fork, driving in the tines 3-4 in. deep, and spacing each set of holes 2-3 in. apart. This gets rather monotonous after a time, and it is best used on small areas.
There are several different types of hand lawn aerators available, and also attachments for lawn mowers, some being fixed at the rear in place of the back roller. The principle is to loosen the hard surface, to admit air, to make for better drainage and better rooting generally.
On a heavy soil it is certainly well worth while improving the aeration by spiking, but there is also another and possibly more important aspect which is that the holes made by spiking can be filled in with a 0.5 - 1 in. dressing of peat, as mentioned earlier, or fresh soil or even fine ashes, as an aid to better root formation.
OTHER PROBLEMS WITH AN ESTABLISHED LAWN
Moss This can be dealt with by watering the lawn with a proprietary moss killer, and those of mercuric preparation are very effective. Follow maker's instructions regarding application.
On a small area rake out the worst of the moss with a springbok rake, although it is sometimes thought that this scatters the spores and results in more moss. The moss problem is worst in damp soil and where the lawn is shaded.
I find that a solution of potassium permanganate, I oz. in a gallon of water, applied to one square yard, is of benefit, but two or three such applications should be given.
Worms Worms can be a problem in a lawn in that they leave many small hills of soil, called 'casts', on the lawn surface in autumn. These can cause a muddy mess after mowing and although worms are very beneficial in soil (they pass soil through their bodies and leave it in a much better condition), their numbers have sometimes to be reduced in a lawn.
One method is to use Mowrah Meal. This is applied at the rate of 4 oz. to the square yard, and is watered in using about a gallon of water to the square yard. It is best applied in damp weather. The effect is to bring worms up to the soil surface and these should then be raked up and taken away. It should not be used where the lawn contains a pond with fish, where the solution may drain into the pond.
An alternative is to use a chlordane preparation which is very effective although more expensive than Mowrah Meal. It is watered on at maker's directions and with this product the worms are killed below ground.
`Bents' The problem of tall bare stems of grass called `Bents' (some grasses are called Bent Grasses) is a common one. These leave an untidy appearance after mowing as they are not cut off by the mower blades but laid flat. After the mower has passed over them they stand up again at varying angles, giving the lawn an untidy appearance.
Sometimes, using the mower at a different angle, i.e. instead of cutting up and down the lawn, going across, or at a slant diagonally, will help matters.
On a small lawn, and where there are not too many `Bents' to deal with, I find it best to cut them off just below the level of the grass using a sharp long-bladed kitchen knife. I realize that this takes time and may be out of the question for a fairly large lawn, but I put the idea forward in case it fits in a particular case.
PROBLEMS IN MAKING A NEW LAWN
If an existing lawn is so poor that it is felt that a fresh start is the best answer do not forget that a full and thorough preparation of the soil is needed in order to sow seed satisfactorily or, for that matter, lay turf.
The point here is that, all being well, one aims to lay a new lawn which is meant to last. It has been said somewhere that the way to get good grass is to mow it for 200 years at least.
`What is meant by preparing a site for a new lawn, or, in other words, what is the minimum work I shall have to do ?' is a commonly asked question.
In brief, an old lawn site is best dug six months before the planned re-sowing. This gives the old turf time to rot down. It should be dug to the full depth of the spade. Remove any large perennial weed roots.
About a month before sowing, and when it is fairly dry, fork through the whole area. Then rake it several times with a wooden rake, remove any stones and leave the plot as level as possible.
To obtain a fine tilth into which the seed will be sown use an iron rake, always when the soil is dry. Rake in the fertilizer dressing during these later-preparation stages.
Another likely question is 'Shall I sow seed or shall I lay turf for my new lawn?'
I think that what attracts many gardeners to laying turf is the fact that there is an instant effect. The main point to consider is that good turf is expensive. By good turf I mean a fine quality, weed-free grass. Lower-quality turf can be purchased, but do not be misguided.
Autumn is the best time to lay the turf, but if the preparation is being done in winter, then lay it in spring, but water freely in a dry spell after laying. I do not like laying turf in summer. It is cheaper to sow seed, and there is the advantage that the quality of grass is easily controlled and coarse-growing grass excluded.
It is true that the newly sown lawn will not be available for heavy use for some months, but on balance I would prefer to sow seed. If you must lay turf prepare the site in the same way as for sowing seed, as described earlier.
To turn back to seed sowing, remember that, with a lawn, everything depends on what you want. If a bowling-green type lawn is required, then the work which has to be put in to keep and maintain such a lawn has to be carried out regularly.
If the lawn is also to be a playing area for children and is
to be used for a lot of sitting out on, and heavy use or wear is likely, then you cannot have a bowling green.
Two different types of grasses are used and needed for two such contrasting types of lawn. With bowling greens very fine, thin-leaved grasses are used and, as is well known, one has to wear rubber over-shoes on a bowling green to prevent damage to the grass and surface.
It is also possible to have a lawn in the in-between category, i.e. one which looks fairly pleasing to the eye and will also stand a fair amount of wear and tear.
All the above presuppose that a new lawn is being laid. In most cases this is not the problem at all, but it is a question of making the best use of, or improving, what one already has, although an existing lawn can be re-prepared and re-sown as described earlier.
Q. How late can I sow grass seed for making a new lawn? A. The two main sowing times for grass seed are September and March. This can be stretched to mean mid-August to mid-September and mid-March to mid-April. One can sow the seed later in spring, but if weather stays very dry, watering is essential. I have re-sown bare patches in a lawn in May, but it is much easier to water a few square yards than a whole new lawn area.
Q. When is it best to lay turf?
A. I prefer autumn, as this gives the turf the rest of the autumn, winter and spring to become established, i.e. to knit together. Much may have to depend on when the site can be prepared and got ready. It may mean that if the preparatory work is started in autumn that you will not be
ready to lay the turf until spring. By all means go ahead on these lines, but, again, if the weather stays dry water freely.
If the weather is very dry and water restrictions prevail it may mean that watering other than by a hose held in the hand is not permissible.
Q. Can I treat my lawn-grass seed with any protective material to prevent birds from eating it?
A. Yes, the proprietary product called Morkit(if it's still produced)can be recommended. It is available from most garden sundries shops.
An alternative is to cover the seed with a thin layer of lawn mowings—if another lawn is already in existence—or to cover with a thin layer of moist peat.
Q. What are the pros and cons of chamomile as a substitute for grass in a lawn?
A. This plant is sometimes used as a lawn, or rather in place of grass for certain types of usage. It is not a substitute for grass in an ordinary lawn, but may be used for odd corners, banks and the like. If a more ambitious use is planned I suggest that a small trial area be planted first, so that an opinion can be formed of its qualities, before using it on a wider scale.
The main points about this plant is that it is low growing, has dark green foliage which retains its colour in dry conditions and does not require very much by way of mowing. It is possible to purchase seed in is. packets (3/4 oz. costs los. and contains about 20,000 seeds, so a is. packet is ample to begin with). Chamomile is listed as Anthemis nobilis in seed catalogues.
Plants can be raised by sowing seed in boxes in spring, and growing them on in a cold frame after transplanting them,
fifty or so to a seed tray. After a period of hardening off, plant out to the permanent positions at a spacing of 4 in. by 4 in. Seed may also be raised by outdoor sowings, and in this case, if room allows, transplant the seedlings as soon as they can be handled, at a spacing of 2 in. square for a few weeks, prior to their being set out in the permanent positions. In either case sow thinly, as the seed is very small.
Chamomile is best suited to light well-drained soils. Always keep the flower heads cut off to prevent the plants becoming straggly, but never mow it hard, like grass; just lightly trim off the tops only. Remember to try a small area first.
Note Dwarf-growing, low-spreading varieties of Thyme—Thymus serphyllum—are sometimes used for a so-called lawn, but are not in my opinion a substitute for grass. Plants can be raised from seed (listed by Thompson & Morgan of Ipswich).