This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
There should be little work left to be done among fruit-trees this month; but often a press of work elsewhere prevents some from doing what is required at the proper time. We have often planted late in April with tolerable success, but would not recommend it to be done if it could be avoided. Mulching, to keep out drought, instead of doing it to keep the roots dry and free from frost (as in autumn planting), will have to be carefully attended to, and watering done if soil should become very dry. Give one good soaking and have done with it: this, when mulching is used, is generally enough. Young trees should not be fastened tightly to walls, etc, until they have sunk as 'far as the soil will allow them; and they should be examined frequently to see that the ties or shreds are not injuring the bark, as they are sure to do if the trees sink much. Give protection to fruit-buds with canvas, Spruce branches, or whatever may be used. Wide copings of boards are much in favour with some, and when they are made to move easily off and on, they give little trouble, and are useful, when fruit is ripe and ripening, for throwing off wet. Figs on walls, wrapt up in straw, etc., may be only partially uncovered, as severe frost may yet be experienced.
Bush fruits, left unpruned to keep them safe from birds, may now have attention. Dustings of lime and white threads crossed over the bushes is practised by some to keep off birds. No hard unbroken surfaces should be left, either among bushes or fruit-trees. If Apricots or Peaches flower very freely, careful thinning of the flower-buds will be of advantage to let the best-placed ones expand freely. On weakly trees a good crop is rarely had when flowers are extra thick.
Lawns, flower-beds, and borders may require a little extra attention this month. Beds requiring manure may be better if supplied with some fresh earth instead. A quantity of road-scrapings, and the parings of walk or road edges, often make a healthy dressing. Deeply working and exposing ground for flowers is quite as necessary as doing it for vegetables. By way of illustration, we have received from a neighbour a quantity of stuff, which was taken from the bottom of an old pond, a few inches of which has been spread over the surface of the beds in the flower-garden, which were previously turned up to the weather. The dressing, which was laid on the surface in frozen lumps, is now broken down like powder, and will be forked evenly into the flower-beds. Though we have plenty of old hot-bed manure on hand, this fresh dressing will act more beneficially, being less likely to give rank growth and few flowers. Heavy soil may be much improved by adding to it a little sand, burnt earth, and vegetable mould. Shrubs should have all dead branches cut out. Limbs taking the lead should be cut within bounds, and where specimen shrubs or trees are wanted, they should be kept well clear of each other. Clipping is now wisely avoided by most cultivators, but a knife unskilfully used is nearly as bad.
When young tops are continually lopped off, the shrubs become matted and stiff, with quantities of dead wood in the hearts of them. Cut well into the stronger wood, which will shoot out with vigour, and the bush or tree (except where cutting right down is done) should not appear as if it had been touched. Gravelling and turning of walks should now be done without delay. Keep them smooth and firm with the roller. Every part of the garden or grounds now should have a cheerful and tidy appearance.
Roses may now be pruned: as a rule, weakly growers should be cut well back, and, if desirable, the stronger shoots layered for rooting to make fresh plants; besides this old practice of layering, the strong wood of Roses forming masses in the beds gives them a grand appearance when they are in flower. Stronger-growing kinds do best with thinning and little shortening; all surface dressings may be forked in at convenience. Roses (with the view of keeping them late) are often pruned as late as the middle of April: stake standards and pillar Roses securely. If annuals are wanted early in summer they may be sown soon, but for a late display late in April is early enough. Hardy annuals coming in flower should be kept free from weeds, the surfaces of the beds kept open, and the plants prevented from becoming matted together, as they would rot in wet weather. Mignonette and Sweet Peas, and all kinds of hardy perennials, may now be sown. Pansy, Polyanthus, Auricula seed, may now be sown - if under a glass light, so much the better. Cover lightly and dust with small coal-ashes, as slugs soon find out the young seedlings. All bedding plants may now be propagated without delay.
Harden those rooted carefully and by degrees, pot the rooted cuttings and keep them growing steadily with as much sun as they will bear, and when well established they may have the lights drawn off in mild weather. Guard against sudden changes; and when plants are wet they suffer more quickly from cold than when they are dry. Carnations, Picotees, Pansies, and similar plants to bloom in pots, may be shifted when the roots have well filled the soil. Topdressing with rich healthy stuff and liquid manure in a weakly state may be given to all gross feeders. Hyacinths, Lily of the Valley, Tulips, and similar plants flowering in pots, will consume quantities of healthy liquid manure. Plants for windows, greenhouses, and frames will now require attention; boxes for windows, if empty, should be well washed, drainage holes examined, and paint used for the outside if necessary. Stocks, Mignonette, Nemophila Insignis, Petunias, Pelargoniums of the Tom Thumb class, Gazanias, CEnotheroe, Heliotrope, are among some of the leading favourites for windows, and all are easily grown; good healthy loam and a little sand suits them; some of the artificial manures used as directed on their cases is of great service to amateurs, especially those in towns.
Greenhouse plants may all be overhauled now that the growing season has commenced. Those which were previously cut back and breaking out fresh may be shifted into larger pots, or the roots reduced and placed into the same size or smaller; Azaleas, Heaths, Epacris, and a number of similar plants, require peat, sand, and charcoal, with little or no loam; many others do well with half loam and peat, and sand to keep the whole open; Acacias, Cytisus, Pimeleas, and Camelias are among this class - the latter does well in turfy loam and charcoal. As a rule, beginners can judge what soil is required by turning the plants out carefully from their pots, and examining the soil they have been growing in, and if there is health and vigour in the roots, fresh material of the same kind may be given if necessary. Keep foliage clean by washing and syringing when it can be safely done, and water with great care after newly potting the plants. Making the soil sodden is destruction to most plants, especially those with fine roots. When potting is done, plenty of drainage should be placed in the bottoms of the pots compactly, and a little moss can often be used over the drainage.
Place some of the rougher part of the material at bottom, and add it round the ball of the plant, leaving no vacant space; plenty of room should be left for watering. Plants grown in peat alone require firm potting and plenty of drainage. If loam is heavy, extra drainage will be required. Water all plants under glass with tepid water, at least as warm as the temperature they are growing in. Give moisture in the morning till nights are warmer. Give air early to all plants requiring it. Firing should only be given when its absence cannot be dispensed with. Use stakes only as necessary evils, and hide them by the branches they are tied to, as far as it can be done. Compactness without stiff formality is desirable. Decaying leaves and dirty pots are very injurious to the health of all plants. When small seeds are sown, little covering should be given, and rather fine soil allowed. Balsams, Cockscombs, Stocks, Asters, Rodanthes, Primulas, and Cinerarias are among those small seeds which will now or very soon require careful sowing, and placed in warmth.