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.
The long-continued frosty weather may have kept some behind with many of the more important garden operations, which will in a great measure be a barrier to success. When land is tenacious and heavy, it will be more difficult to deal with than soil of a light warm nature. However, by a little perseverance, much can be done with clay soil; and, when well managed, it often carries the best of crops. As an example: we saw at Frogmore, last season, large breadths of ground which had been well trenched for sowing and planting, but was so much like iron that it appeared impossible to work it by any means. The day before it was required for cropping, copious waterings were given all over the surfaces, and the following day the soil broke down freely like powder, and was in excellent order for any purpose. When weather is wet, this kind of ground can hardly be touched. Every opportunity should be taken to break the surface as well as possible, and the seeds should be sown in lines, covering them with any waste soil finely sifted, which we have often recommended to be kept in store in dry quarters till wanted. We have often seen drills made for Peas, Beans, etc, with the spade; the seeds sown and covered with charcoal dust or leaf-mould, and the crops turn out amazingly fine.
Planting of Cabbage, Cauliflower, or similar plants, may be done in heavy land by making holes with a trowel, placing a handful or two of good soil to each plant as the work goes on: a little soot in this soil makes uncomfortable quarters for grubs, which often destroy Cabbage and Cauliflower. The ground for main crop of Carrots should now be in good order; a good coating of lime and soot may be useful in keeping grubs in check - the surface well broken and drills drawn a foot or 14 inches apart; on poor sandy soil less will do. A good crop of Carrots in gardens is seldom met with, and the free use of lime used in preparing the ground through the winter, and other means which are sometimes used with success, often amount to more than good Carrots can be bought for in the districts where they grow without any attention whatever. Asparagus may now be sown for keeping up a stock of roots; light rich soil of a sandy mixture is the best. Artichokes, globe, should now be looked over, forking among the plants and breaking over the ground without injuring the roots: suckers, when they can be had, may be planted for late supplies.
Jerusalem Artichokes, if not already planted, may be got in at once, if treated like Potatoes; keeping them in single rows, and staking up the stems if they get top-heavy, is all they require. When the rows are thickly planted, the produce is much smaller for want of light and air. Broad Beans may again be planted for a succession, if the soil for them is light. Mulching may be of great service as the season advances. Beet will require attention soon; though it often does well on any soil, the produce is very stringy and tough when grown on shallow indifferent soil. We again repeat that rank manure, newly given to roots of all kinds, is their ruin. Silver Beet makes a useful substitute in winter for Spinach, but it need not be sown for some time. Broccoli, Brussels Sprouts, Cabbage, Cauliflower, and Lettuces may be sown as formerly advised. Birds and slugs will be great enemies to the young plants as they begin to vegetate. Where Onions are liable to be eaten by grubs, a quantity of last season's bulbs may be planted, dusting them with soot in showery weather. Herbs of all kinds may be sown on a dry sheltered border. Basil will require heat and careful hardening off before being planted on a warm border.
Tomatoes, sown in a little warmth and liberally treated, will give a good late supply. If grown in pots of large size, and plunged at the base of a wall or any sunny spot well sheltered from wind, they will produce freely. Large established plants to begin with is of great importance. Radishes and Salads of all kinds require to be sown often at this season; if watering the seeds is necessary, it should be done in the morning, till the nights are warmer. Quick growth, and no check given, prevents toughness and rank flavour. Rhubarb seed may be sown in a warm position, where the soil is free and dry. If blanched stalks are preferred, pets or boxes may be placed over the crowns, keeping out the most of the air; it is thus made more tender and juicy. Spinach, round, may be sown between other crops, or bushes if ground is scarce. To have fine large leaves, plenty of rotten manure must be allowed; sow thinly. The plants should be at least 4 inches apart in the rows.
Turnips may be sown in small quantities still, dusting wood-ashes or soot over the leaves as they come through the ground, to prevent the ravages of "fly." If not already done, the main crop of Celery should be sown, either in a frame or under a handlight. Do not let the young plants become matted or dry at the root; shelter them from cutting winds, but increase light and air as they grow; and for pricking them out on, let the bed be, if possible, solid rotten manure, with 2 inches of light soil over the surface; and when the roots are well established, there will be no difficulty in lifting large balls with the plants, when placed in the trenches, in June or July. Ground on which is grown the latest Broccoli does well for the Celery trenches. One or two sowings of Peas may be got in during the month. Stake those growing before they fall over, and keep the hoe going freely among all growing crops; order and neatness should prevail everywhere. Fine raking of surfaces is not to be recommended in the vegetable garden. Melons and Cucumbers will now require attention, keeping them trained out regular over the beds, keeping the principal shoots a good distance apart, so that the bearing-shoots are not crowded.
In one light, two leading shoots of Melons trained each way, and the tops taken off just before they reach the sides of frame, will do; and two or three side-shoots will be pushed from each leading one, which will require stopping as soon as the fruit appears: all other shoots not required should be rubbed off before they rob the plants. Cucumbers will require more pinching than Melons, as more fruit is taken, and none (except one or two for seed, which rob the plants very much) allowed to ripen. Two Cucumbers 10 inches long are more valuable than one of 20 inches. When the fruits are allowed to become yellow at the ends, they are almost worthless. Heat kept up by linings or otherwise should be not less than 65° at night; 75° with a little air on all night is not too much. Shutting up the frame early on sunny afternoons, after sprinkling all the beds with tepid water, will promote free growth in newly-turned-out plants. Air, avoiding cutting winds, is indispensable to success when the plants become established.
Fruit-trees may require disbudding in southern localities before the month is out. If done early and at different times, the tree will receive no check: great quantities of foliage cut off at one time gives a severe check to the trees. All shoots growing out from the walls should be taken clean off.
Asters, Stocks, Larkspurs, Convolvulus, Tropaeolum Canariensis (the two latter for climbing on old tree-stumps, or vacant spaces on walls), Marigold (French and African), Saponaria Calabrica, Rhodanthe Man-glesii, Humea elegans (for large plants), maybe sown in a frame at once, using fine light soil, and covering the small seeds very slightly. These are all useful for decorating borders, etc, and can be procured and grown where ordinary bedding-plants cannot be kept easily through the winter; timely attention, when the plants are fit to handle, should be given to get them pricked out before they become matted; a small panful of each will fill a large space when well managed. Cockscombs, Balsams, Globe Amaranthus, and similar plants, to be grown in pots for decorating glass structures, may be sown now in a little heat; a close temperature will ruin the young plants. To have them sturdy and vigorous, they require plenty of light and air, as well as a little bottom heat. Use tepid water for every plant when in heat, even although they are of a very hardy nature.
Every border and lawn should now have a clean fresh appearance. Grass seeds sown now will start into growth freely, but birds must be kept off, or weeds may only appear, and the vendor of the grass seeds be blamed for supplying a spurious article. Be it remembered that where grass does not occupy the ground, weeds of the worst kind will speedily show themselves. Dustings of guano and soot in showery weather will strengthen the growth of weakly grass. All grass edgings may now be neatly pared, taking care not to unnecessarily reduce the turf edgings, as when narrow they are mean in appearance, and more difficult to keep tidy.
Pot Carnation and Picotees, if they are to be flowered in pots, and plant out those to be flowered in the borders ; fresh sandy loam, with a little decayed cow-dung in it, suits them well. Take care of bedding plants, which may be hardening off to be turned out next month; doing it gradually will be the safest way, as sudden changes are very injurious. Dahlias, being tender, will stand very little cold wind. Chrysanthemums growing in small pots should be shifted into larger sizes, as the pots become filled with roots. It is now a good time to take off cuttings for small specimens, or to divide large plants, which is an easy method of growing them for decorating either greenhouse or sheltered borders. In the north they seldom come in early enough for outside work. Ranunculus, and all other tuberous or bulbous plants coming through the ground, should have the surface soil well broken, and a little earth slightly pressed to each stem. Protection from frost (even for those which are hardy) will be of great service in securing a good bloom. Pansies for bedding may be planted out in rich cool soil. Violas Cornuta, Alba, Lutea, and Amcena, are excellent on deep rich soil; and being so hardy, they are easily managed. All the hardier bedding plants may be planted out soon.
All plants for summer flowering in pots should be examined and potted if they have plenty of roots; some in unhealthy soil may have the ball reduced, and fresh drainage and healthy soil given. Fuchsias, Calceolarias (shrubby), Zonale Pelargoniums, Aloysias, and Heliotropes, are among the leading kinds grown by amateurs. Surfacing healthy roots with rotten manure and fresh sandy loam may be done with advantage, but care must be exercised not to close up the roots from air, as is so often done by unsuccessful cultivators of orchard-house trees. Vines, Figs, and many other fruits are ruined by this kind of surface-clogging. Air into the soil is as necessary as air to the foliage. Manure-water does much for vigorous healthy growth, but it should always be used in a clear state. Soot and sheep's dung make a simple but powerful stimulant; stir it well for a day or two, and let it settle to the bottom, using enough to colour the water. Any plants grown in peat, such as Azaleas or Heaths, do not require manure-water, though a little clear soot-water can be used with advantage by experienced men. More water will now be required at the roots of plants as the season advances; give it in the morning, except where structures are subject to drying heat.
When nights are warm, the afternoon is the time to water. Keep all surfaces of pots clean and well stirred, and tolerate no dirty pots. Look after insects and other vermin among all plants.