The Cucurbita Genus includes Greenhouse Frame Cucumbers, Gherkins and Ridge Cucumbers which originate in India and have been grown in this country since the 16th Century but it also includes the three groups of vegetables Marrow, Pumpkins and Squashes which originate in North, Central and South America. The plants are very tender and not frost hardy, while the fruits contain a high percentage of water. Warmth and moisture are necessary for successful cultivation.
Sowing the Seed
Seed for marrow, pumpkins and squashes should be sown early to mid-May under glass or in situ after frost damage is past, not earlier than the end of May, depending on the area.
We find the best plants are obtained by sowing under glass in 10cm pots; two seeds are sown per pot and the weaker seedling is ultimately removed. The seeds should be inserted on edge into the compost. A peaty compost is best with the seedlings kept well watered. Spray the surface with Fruit & Vegtable Disease Control to prevent damping off.
When the seedlings have developed four to six mature leaves the plants can be hardened off prior to planting out. It is important to avoid too much root disturbance when planting out.
Preparation of Soil and Cultivation
A rich well manured soil is needed, mound up to receive the plants. A surface dressing of sulphate of potash, bonemeal and superphosphate can be useful. It is important to use a deeply dug site with plenty of room available for the plants to trail and spread. Plant out the pot grown plants 1.0 ñ 1.25 metres apart on open ground each on a mound of richly manured soil. If the plant is in a small hollow on its mound this helps with watering. If watered regularly the plants will grow fast, particularly after flowering. The soil should be pre-treated against slugs and snails or slug pellets scattered.
When insects are not active it may be necessary to hand pollinate to encourage fruits. As fruits develop they should be kept clear of soil damage by standing them on small mats of plastic materials or sheet glass. As the plants are voracious feeders they should be frequently fed with potash rich liquid feeds but care should be taken not to splash the plant stems to avoid the tendency to rot.
For exhibition purposes the marrows are shown as a matching pair or three of a kind according to the schedule.
Shop marrows are grown by allowing two or three adjacent fruits to develop and pinching out the leader beyond these selected fruits. All other leaders are removed.
In a show the marrow is a 15 point vegetable (with 5 points for condition, 5 points for size, shape or colour and 5 points for uniformity). The Royal Horticultural Society include Squashes and other edible Cucurbits in the same class but most shows just specify marrows. The ideal show marrow is not usually more than 30cm in length. Where marrows are specified in a schedule, Squashes and other Cucurbits can be introduced under the Any Other Vegetable class.
Varieties commonly grown are All Green Bush, Long Green Bush, Long Green Trailing, Tiger Cross, Zebra Cross, Tender and True, Clarita, Early Gem and Table Dainty. The varieties for shows are selected with the show schedule in mind and Table Dainty is popular because a matching pair about 20cm in length can be readily obtained while heavyweight marrows more often occur with the Green Bush or trailing varieties.
Pumpkins are becoming more popular because of specialist pumpkin shows and show classes for the heaviest pumpkin.
Originating in America, they are now part and parcel of Halloween festivities. Growing conditions are the same as detailed for marrows and the best results are obtained with heavily manured rich soil. Plenty of room is needed as the fruit can be large and the plants produce long trailing shoots. Size can be encouraged by limiting the number of fruits on each vine by pinching out the shoots in a similar way to marrows. Fruit has to be removed from the vines before the autumn frosts and stored in dry, frost-free conditions.
Many varieties are now grown depending on the results required. If size and weight are the only requirements then it is important to use Giant Pumpkin seed, selected to produce weights of about 200 kilogram, which is obtainable from the USA through specialist sources and available from the UK seedsmen as Atlantic Giant. Before these American varieties arrived the heaviest pumpkins were round, known as Hundredweight and Mammoth.
In celebrating Independence Day the Americans cook pumpkin sweets to accompany roast turkey while in this country pumpkins are hollowed out to produce pumpkin pie from the fruit and lanterns from the shells remaining. We were recently sent some seeds of Queensland Blue Pumpkin from Australia. The propagated easily and produced plants which trailed across our vegetable plots and produced greenish blue medium sized fruits prolifically. The fruit of these pumpkins contains less water than most and is used in Australia to make pumpkin cakes similar to our potato cakes. From these fruits we made a delicious rich soup and obtained slices of pumpkin which were fried or grilled, similarly to parsnips.
There are a number of smaller pumpkins such as Jack-be-Little, Crown Prince, Jackpot and Mavis Sweetner which are widely grown and have culinary uses.
Squashes are grown in the same way and under the same conditions as pumpkins and marrows and produce fruit in a variety of smaller shapes and sizes. Among the commoner varieties are Butterball, Buttercup, Hubbards Squash with variants Golden and Green, Pattipan, Scalop Squash and Turks Turban which is mainly grown for its decorative effect.