A new lawn which has been grown from seed may need its first cut by the end of mid-spring, if conditions for germination and growth have been good. The grass blades will then be about 5cm (2in) long. Before cutting, you can roll it once, with a light roller, to firm the roots of the young plants into the soil. Set the mower blades high, make sure they are razor sharp and then take only the top off the grass, about 1cm (1/2in).
Mowing of an established lawn can get into full swing, as the grass will be growing quickly, and you can reduce the height of cut to 0.5-1cm (1/4-1/2in) by the beginning of late spring. Mow the lawn with the collecting box attached, otherwise the clippings will choke the sward. Hot, dry weather is the only time the mowings can be left; they will then conserve moisture. If you have time, brushing with a stiff broom before you mow will maintain good aeration of the turf and prevent the build-up of a mat of vegetation on the soil surface.
Established lawns can be fed, using a compound lawn fertilizer or, if you want quick but not long-lasting results, sulphate of ammonia, 15g (1/2oz) in 4.5L (1 gal) of water, put on with a spray or with a watering-can with a rose. Dry fertilizer must be put on evenly, at the rate recommended by the manufacturers, as a patchy application will only result in burning the grass and quite possibly killing it. Another requirement is moist soil, with the chance of rain within a few hours.
Sweetpeas planted in early spring after being overwintered will begin to elongate rapidly and should be supplied with 2.5m (8ft) stakes, such as bamboo canes, one to each stem, to which they can be attached with sweetpea rings. Attach twine or wire to the tops of the canes along the row and support each end cane with a strong stake. Tendrils and side-shoots should be taken off as they appear. Tendrils take the place of a leaflet; side-shoots grow from the join between the main stem and a leaf stem.
The new one can be started in earnest, as weeds germinate along with your hardy annuals and new lawn. Give it a base of brushwood or bricks spaced well apart, so that air can get underneath, and surround it with a wooden framework, straw bales, rigid plastic, or black plastic sheet. Build it 120-150cm (48-60in) high, about the same width and any convenient length. Sticking a pole in the centre will ensure that there is a kind of chimney going through the heap, up which air can be drawn when you withdraw the pole at the finish of building.
The main weed problem will be in the annual beds and patches and on the seed-bed provided for your new lawn. If both areas were not properly fallowed, there will be as many, if not more, weed seeds as cultivated seedlings, germinating merrily and growing faster. You can water on a solution of a new lawn weedkiller about a week after the grass germinates, otherwise you will have to remove the worst weeds by hand. However, with large areas this is impracticable, but usually as the grass grows and is cut, the weeds will be overcome, as these annual kinds cannot compete with the grass and withstand frequent cutting at the same time.
Amongst the annuals, handweeding will be necessary and with the smaller areas is quite practicable. Elsewhere in the garden, hoeing or handweeding will keep aliens at bay, if your perennials and groundcovers are not sufficiently closely planted to prevent their obtaining a toe-hold.
This is a good time of the year to eradicate weeds on paths; you can either water them with a weedkiller which lasts for six months, or you can remove them by hand and then apply one which lasts a year.
The half-hardy annuals and bedding plants sown in artificial heat two or three weeks ago will need to be pricked out into boxes. Seeds sown in frames may have germinated sufficiently well for these seedlings also to need pricking out.
The corms and tubers that you started in early spring in moist peat can be transferred to individual pots, 12.5-17.5cm (5-7in) in diameter for all but the achimenes. Do not completely bury the tuber or corm and use a rather peaty compost. Achimenes can be very slow to sprout but when the shoots are about 5cm (2in) tall, transfer the tubercles to 15 or 17.5cm (6 or 7in) pots and plant them about 7.5cm (3in) apart.
Rooted cuttings such as those of early- and late-lowering chrysanthemums and pelargoniums can be potted or potted on. Be guided by the state of the roots; if they have filled the soil ball and are just spreading round the outside, the plants are ready for new pots, about 2.5-4cm (1-1/2in) in diameter larger than the old ones. Roots coming through the drainage hole or wound round and round the base mean the plant is long overdue for a larger pot.
Late-flowering chrysanthemums, if the cuttings were taken in early or mid-winter, may be ready to go into their final pots, 23cm (9in) in diameter. Use J.I. Potting compost No. 3. Such potting is likely to be necessary at the end of mid-spring.
Pricked-out seedlings may also need to be moved into their first pots, using a size which the roots can fit into comfortably without being cramped. If they have one or two long roots, with plenty of shorter, finer ones, it does no harm to shorten the long ones to a convenient length.
Repot or topdress those plants permanently in containers which were not done in early spring.
Early-flowering chrysanthemums can be stopped in the same way and for the same reasons as late-flowering kinds.
Dahlias, fuchsias and delphiniums can be propagated from cuttings. The dahlias put to sprout in early spring should have long enough shoots by now to provide cuttings; use those about 5-7.5cm (2-3in) long. If you cut them off to leave a stub, this will produce more shoots later on.
Fuchsia cuttings can be made in the same way from the newly produced shoot. Outdoor delphiniums should also have sprouted by now and, if the slugs have left any, the same length cuttings can be made from the shoots and put in sandy compost in the frame. It may still be possible to take cuttings of early-flowering chrysanthemums.
Greenhouse plants will be needing more and more water; there are various ways of doing this according to the equipment and time you have available.
Continue to increase the ventilation in the greenhouse as the weather gets warmer. Turn the heat off when possible, but make sure the seedlings and rooted cuttings do not catch a chill. Frame lights can be raised during the day, or removed altogether in sunny weather.
Mid-spring sees the big hatch of insect pests, especially greenfly, the universal pest of plants. Other sucking insect pests such as leaf suckers and leaf-hoppers also appear from tiny overwintering eggs on weeds, bushes and trees, and caterpillars of all kinds will begin to eat leaves, as well as stems and, eventually, flowers. Leatherjackets may make a final onslaught on lawn grasses before they pupate – they account for pale brown patches of dead grass on many lawns in spring. Diseases will not be quite so troublesome for a while yet, apart from grey mould (Botrytis filtered), but peonies will need watching for blight and bud disease at this time.
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