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.
Keep up a genial growing atmosphere, not allowing the temperature to sink much below 70° at night; give air in the early part of the day, and shut up early with, same heat, and lessen the moisture in the soil and atmosphere as the season becomes more dull and sunless; but where the roots are near the hot pipes, see that over-dryness of soil is not allowed. Stop them at every joint, and do not allow them to become overcrowded, which produces a thin weakly foliage, which is much more apt to damp off as the weather becomes more damp and sunless. Do not allow them to bear too much fruit at one time.
We have now long damp nights and dull sunless days, conditions very trying to Cucumbers. The temperature should range from 65° at night to 70° by day, with a few degrees more when the sun shines. Water and moisture in the air must be more sparingly applied: give a little air on all favourable occasions. Do not allow the plants to bear more fruit than are absolutely required; for if heavily cropped now, it will weaken and injure for future bearing. Keep young growths regularly stopped, and do not allow any crowding of foliage. If green-fly attack them, destroy it by two moderate smokings with tobacco on two consecutive nights.
See last month's Calendar, and avoid hard forcing in very cold sunle?s weather, or the leaves will become thin, and the whole plants weakened. When the weather is severe, it is very desirable to cover the surface of the glass, and fire more moderately.
Sow for early spring crops in the same way as directed for melons, only use a lighter and richer soil. Keep the temperature in the Cucumber-house in bearing from 65° to 70°, according as the weather is cold or mild. When cold, apply covering to the glass, if possible; it saves fire, and is better for the crop. Do not allow the plants to bear too many Cucumbers at one time, or it will weaken them. Keep the bed of soil moderately moist, and water occasionally with manure-water. Give more or less air according to the weather daily. Do not allow the leaves and young growths to become crowded, and stop the latter at every joint. Should green-fly attack them, fumigate moderately on two successive evenings. If fumigated severely, the young tender leaves are likely to be injured.
See last month's directions regarding those now in bearing. Those sown in January will be ready to plant this month. Let the soil be composed of two parts fresh loam and one part leaf-mould or very rotten dung. If to be grown on trellis in Cucumber-houses, plant them 2 feet apart, and train the leader without being stopped till it grows 4 feet, but stop the lateral growths at every joint. Range the night temperature at 70°. Give a little air every day, and shut up early with sun-heat. Keep them steadily moist at the root with water at 85°. Sow about the middle of the month for later crops.
Look over free-growing plants every two or three days and stop them at every joint. Remove all deformed fruit, and do not let them bear too many at a time. After a season of dull weather, shade slightly for a time in the middle of the day. Range the night temperature about 70°, and shut up with 15° more from sun-heat in the afternoon. Water those in full bearing with rnanure-water, and top-dress with fresh loam and horse-droppings.
The temperature for bearing plants may range a few degrees higher than the temperature formerly directed. Let the border of those in full bearing be mulched with rotten manure and turfy loam in equal proportions. Shut up early in the afternoon, and syringe with tepid water after bright days. Thin off all deformed fruit, and pinch the laterals at every leaf. Keep the border regularly and moderately moist; sow and plant for succession crops.
This is a good time to plant for summer and'autumn supply. Those which have been bearing heavily for a considerable time back, will now be benefited by a top-dressing of equal parts loam and horse-droppings. Where spring-planted crops are now equal to the demand, the former may be pulled out and their place occupied with Melons, where such is necessary. See that those now bearing heavily are well supplied with water. Syringe them at shutting-up time, and if thrip appears fumigate on two successive nights with tobacco.
A quantity, according to the demand, may now be planted out in the southern part of the kingdom in cold frames where flower-garden plants have been stored. A foot of half-rotten manure or leaves, or both, mixed together, being placed in the bottom, with 8 inches of rich soil, is all the preparation necessary to their bearing freely till the middle or end of September. More artificial warmth is needed for Scotland. Top-dress the beds of those that have been bearing heavily for some time, and water with manure - water. Syringe occasionally with clean soot-water to keep spider and thrips in check.
Syringe regularly at shutting - up time, and see that all plants in full bearing are well supplied with moisture at the root. Give those which have been bearing freely for a length of time a rich top-dressing, and do not allow them to bear very heavily for a week or two, and they will soon renew their vigour and bear fine fruit again. Impregnate a few fruit for seed, choosing fruit that show signs of being fine. Look over all free-growing plants every two or three days, and stop and regulate the young growths, allowing no more foliage than is just sufficient to occupy the space without crowding.
Those that are in full bearing will still require a good supply of water. Any that show signs of debility from heavy cropping should have all deformed fruit removed, and be allowed to bring only a few to maturity for some time, which, with the aid of rich top - dressing and watering, will cause them to renew their strength. Sow about the middle of the month for winter crops.