This section is from the book "A Dictionary Of Modern Gardening", by George William Johnson, David Landreth. Also available from Amazon: The Winter Harvest Handbook: Year Round Vegetable Production Using Deep Organic Techniques and Unheated Greenhouses.
For the production of seed, some fruit of the earliest raised crops must be left: of these the finest and firmest should be selected, the choice being guided by the circumstances, as are mentioned for cucumbers. No two varieties should be grown in the same frame, either when the seed is an object, for then it would be contaminated; or if the fruit is alone required; for their growth and vigour almost always differing, different treatment is required by each. Neither should cucumbers or gourds be allowed to vegetate in such a situation, as to risk mutual impregnation by insects. Both of the melon and cucumber, such seed only should be kept as sinks freely to the bottom of water. Seed is best for sowing when three or four years old; if less than two, the plants raised from it are apt to produce a super-luxuriance of vine, and a multitude of male blossoms. If new seed is unavoidably employed, it should be hung in a paper or phial near the fire until wanted, or be carried in the pocket for three or four weeks. If, on the contrary, the seed is very old, it should be soaked in milk-warm water for two or three hours before sowing.
When twenty years old it has been known to produce fruitful plants.
For these, plants are required from sowings of the middle of March, April, or early in May, and whose fitness for planting out, is marked by the rough leaf, etc, as intimated before.
The bed must be four and a half feet wide, in length proportionate to the number of glasses, which must be at least four feet apart; and, eight barrow loads of dung being allowed to each glass, it will be about two and a half feet high. It may be founded in a trench, if the soil is dry, but it is best constructed on the surface. The earthing, planting, and other points of management are precisely the same as for the frame crops. The temperature need not, however, be so high, the maximum required being 70°, but it must never sink below 65°, which may easily be accomplished by linings, etc. The runners must not be allowed to extend from beneath the glasses until June, or the weather has become genial and settled, but be kept within as noticed for cucumbers. When allowed to escape, all dwindled or supervigor-ous shoots must be removed, and the training be as regular as for those in the frames. The glasses raised upon props must, however, be kept constantly over the centre as a shelter to the capital parts.
The bed requires to be hooped over for the support of mats in cold or wet weather. If paper-frames are employed, the most unremitting attention is required, the plants being very apt to spindle under them. They may, however, be employed with advantage in the place of mats for sheltering and shading. If the weather is at all unfavourable at the time the fruit is approaching maturity, it is highly advantageous to place hand-glasses over those that are growing exterior to the original one. The latest fruit seldom ripen even with the greatest care and attention, unless there are spare frames to inclose them entirely; those which do not, are employed in pickling.
For a tolerable supply throughout the season, a small family requires one three-light frame, and three hand-glasses; these together will yield on the average thirty or forty melons. The largest establishment will not require more than four times as many.
 
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