These are members of the Cucumber Family belonging mostly to the genera Cucurbita, Lagenaria, and Luffa. By far the largest numbers of varying ornamental hard-shelled gourds are those originating from Cucurbita pepo ovifera which is the yellow-flowered gourd, easily distinguished from the white-flowered Lagenaria types which take a longer growing season to mature properly. Gourds can be grown in any good soil similar to that in the vegetable garden. They need as long a growing period as possible, especially L. siceraria, the reason why some gardeners in the North just do not have a sufficient number of days of hot sunshine to mature the fruits. On the other hand, Cucurbita pepo ovifera ripens easily in Zones 3 and 4.
One should be certain at the start to obtain good viable seed from a reliable source. Seeds-men are selling gourds in 2 ways. The first is “mixed,” that is, several varieties of differently shaped gourds have been used for seed purposes and one can obtain many interesting gourds from such a package. On the other hand, the unscrupulous person will mix seed from a lot of inferior-shaped types together, and still sell them as “mixed” and be correct in so doing. Other seeds-men who have sources of seed from pure stands of Nest Egg, Striped Pear, Spoon or Miniature Bottle, will sell seeds of these types and the gardener has reasonable assurance they will produce gourds true to name. It really pays to purchase well-grown reliable seeds of this type regardless of whether they are sold as individual varieties or as “Super Hybrids Mixed.” Germination is helped if the seed is soaked in warm water for 12-48 hours before sowing. Seed will keep at least a year, (usually several), if put in a dry cool place.
When to Plant Gourds
Good seed should be sown in hills, 6-8 seeds per hill, after all the dangers of frost are over. It is unwise to sow too early for they simply will not grow until the soil warms up. They can be started in pots in the greenhouse 3 weeks before they are to be set out in the garden, thus gaining a few weeks on the ones planted directly in the soil. However, the roots should not be disturbed in transplanting, but the entire pot full of undisturbed roots and soil set out in one careful operation. Certainly this is the way to plant Lagenaria varieties especially in the North, and even then there may not be sufficient time for the fruit to ripen properly. All gourds should be grown in full sunshine, not in the shade.
Theoretically gourds should be trained on a trellis, up some chicken wire or over some brush to keep the fruits off the ground. Most of us do not have time for that and are willing to take our chances with a few of the fruits being marred on the ground. Seeds might be planted twice their length deep in good, friable soil. When seedlings are up the hills might be thinned to about 4 plants per hill, the hills being about 8 ft. apart. If the seed was “mixed” remember that the seedlings will show variation and one should not remove all the smallest seedlings, because these might just be the varieties with the smallest and most interesting fruits.
Fertilizers should be applied as for pumpkins and squash. The roots of gourds are very close to the soil surface hence in hoeing one should be careful not to disturb the roots. They need ample water and should be given plenty of it during drought periods.
Pruning the vines can increase the number of fruits borne per vine. The main stem should be allowed to grow until it is to ft. long, when the end can be removed. It is on this part that mostly male flowers are borne. The lateral shoots bear mostly pistillate flowers. If the end bud of the main shoot is snipped off after the shoot is to ft. long, then the first lateral shoots have the main end buds taken off them when each shoot has developed about 4 leaves, this is sufficient for the pruning. Any sub-lateral shoots, developing after this, are allowed to grow at will. This type of pruning can aid in the production of more fruits.
Gourds must be thoroughly ripened on the vine before they are picked, for if picked when green or immature they will soon rot. For the varieties of Cucurbita pepo ovifera, the stem where the gourd is attached to the vine should be watched. When this starts to shrivel and dry up, then the gourd should be picked. It is best to cut them off the vine with shears, saving a few inches of stem on each gourd, rather than roughly tearing them off the vine, often severing the stem right at the end of the gourd. If roughly done, this can injure the gourd end just enough to allow disease to enter and the fruit will rot.
The gourds should not be left out in the field, but rather brought in and washed, often with a mild disinfectant, and set aside a few days to dry thoroughly. The idea is to wash off any soil or impurities which may have become attached to the shell. After a few days they can then be carefully waxed with any floor paste wax, and set aside for use as ornaments. Some will undoubtedly rot, but the majority, if picked when fully mature, will harden nicely and can be used for years.
The white gourds of Lagenaria siceraria should be even more carefully watched and picked just before they start to turn yellowish from too much sunshine. In the South these calabash gourds are easy to grow and to mature, but in the North it is very difficult to grow them properly. They include the Bottle, Depressed Bottle, Powder Horn, Dipper and Kettle.
Nest and Dolphin types along with many others are 2 species have green fruits with a rind that is not hard, but dry and papery. These can be a foot long and also take a long growing season. The inside pulp can be dried out and then used as a dish cloth.
It is of interest to note that markings can be made on the shells of any of these gourds when they are half ripe and growing on the vines. Thus, initials, characters, rough line sketches made at this time, eventually look as if they had actually grown on the shell. Also wires, strings or even containers can be placed around the developing fruits in such ways as to permanently change and control the shape. Thus, it is possible to have a square gourd (forced to grow within some confining square metal or concrete box). These then are the popular hard-shelled gourds.