This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
The fruit of the Marrow (Cucurbita Pepo ovifera) is becoming more and more important as an article of food. As a forcing plant in the bush form it is very useful. Those who employ lights and boxes for raising Lettuces during the winter will find the Marrow a valuable crop with which to fill them during the spring months, particularly if there are pits with hot water under. If not, a bed of manure to give the plants a start, and night coverings of litter or mats will bring them on to fruit in June, a good time before anything can be on the market from those sown out-of-doors. If trailing Marrows are put under the lights, then the rows can be 4 yd. apart, and as soon as May is out the boxes can be lifted to allow the shoots to run out, and they will soon cover the ground. To grow Marrows successfully when planted on hot beds of manure, water must be handy, in quantities enough to keep them moist in any weather. In the evening after sunset is the time to get the best results from watering. If the Bush variety of Marrow is grown, then the white is the better for growing under lights.
The Green Bush Marrow is largely grown as a field crop. The seed is sown during May in rows 3 ft. 6 in. or 4 ft. apart. Two or three seeds are put in a place in case one or two should fail. The seeds are covered with 1/2 in. of soil, and are so arranged as to be 3 ft. apart in the rows. When once above ground it is astonishing how rapidly the plants grow. Where more than one seed has come up in a place they are singled, and no more attention is needed except hoeing. This can be done principally with the horse hoe unless the crop is "middled" with something else, which it may be, either with Lettuce or Spinach or three drills of Radishes, where the land is light and good enough. [W. G. L].
So large an area as 200 to 250 ac. of Marrows in the Evesham district may appear an exaggeration, but probably the estimate is too low; there are so many who grow them, that if they averaged only 1/8 ac. each there would be a larger area acounted for than that mentioned.
Sometimes the Marrow plants are raised from seed sown in pots as described for Cucumbers; but more usually the seed is sown where the plants are to grow and fruit. In the latter case holes - as for ridge Cucumbers - are made at certain distances apart, the distances depending on whether the ordinary rambling plant be grown, or whether they be "bush" Marrows; the latter being compact and very fruitful plants. The latter are usually planted about 5 ft. apart, but the former are given twice the space. The bush Marrows have almost displaced the rambling species. One or two forkfuls of manure is placed in each hole, the soil returned over it and forming a small mound, a ring of metal (usually zinc) about 12 in. in diameter and 3 or 4 in. in depth is placed thereon, three or four seeds are sown, and a disk of glass placed over the ring. This is done about the end of April. Some covering is applied nightly until danger from frost is past; and when the young plants appear above the soil the weaker ones are destroyed. With the warmer days and nights of June the glass is entirely removed, and the Marrow plants fully exposed. Marrows are usually sent to market in bushel hampers or "pots", and are sold in that way; so that 2s., say, may be given for a "pot" containing twenty small marrows or ten medium-sized ones. (J. U].