Pumpkins Zucchini Melons, & Cucumbers, these are the Cucurbits, and they always attract the most confusion and questions when it comes to seed saving.
The best way to approach it is at the beginning of the growing season so that you can plan what you grow and what to do when it comes to saving seeds.
My biggest tip if you want to save seeds from The Cucurbits - ONLY GROW ONE TYPE from each group, that way there is no confusion with cross- pollination.
When it comes to knowing which group it comes from ASK that's what I'm here for, but use this as a general guide.
Some species are simple --- cucumbers are all in the same species (
Cucumis sativus) while most melons are in a related but distinct species (
Cucumis melo.) Watermelons are in their own species ---
Citrillus vulgaris. So, if you want to save cucumber seeds, plan to only grow one variety of cucumber in your garden. Same with melons, though you can grow watermelons and canteloupes side by side with no problems since they're in different species.
There are actually four species which cover the vegetables we call pumpkins/squashes - one from each group may be grown together without crossing
Curcurbita maxima
These are generally the big pumkins. Jarrahdale; Qld. Blue; Atlantic Giant; Golden Nugget; Baby Blue; Triamble; Hubbard; Turban; Banana; and Buttercup
Queensland Blue - - large pumpkin, dark slate grey ribbed skin, sweet deep orange flesh, top keeper
Triamble – large 3-lobed, tough grey skin, deep orange flesh, sweet, firm & dry
Ironbark – hard skin, dry orange flesh
Australian Butter – similar to Qld Blue, with yellow skin, mildew resistant
Blue Banana – thick firm orange-yellow flesh, pale blue skin, approx 15 x 40 cms, does well in dry, good keeper
Curcurbita moschata
Butternuts; Japs; Crookneck (Golden cushaw), Grammas.
Paw Paw gramma – sweet, thick deep yellow flesh with nutty flavour, trailing vine, fruit to 4kg, appearance of pawpaw, disease resistant
Bink’s gramma – Robena calls this one of the best taste wise
Dennis’ giant butternut – a fat butternut
Dennis’ trombone – green skin, trombone shape with long neck, sweet & used for pies, scones, soup etc
Long neck butternut – long necks mean more solid flesh with no cavity
Curcurbita pepo
all summer squashes (zucchini, yellow squashes, etc.), some of the gourds, patty pan, delicata, summer crookneck squash
Table Gem squash – heavy cropping, acorn shaped fruit approx 6”, dark green rind with thick dry orange flesh, bush, allow to mature fully before picking
Spaghetti squash – vigorous vine, cylindrical fruit to 12”, yellow, spaghetti like flesh, bake or boil (and use flesh as spaghetti, with sauce of choice)
Kumu Kumi also known as 'Kamo Kamo' by Maori people.
Curcurbita mixta
Windsor Black pumpkin – vigorous vine, dark skin, firm dry orange flesh
pumpkin like Green Striped Cushaw but this species is not common in Australia
One thing to remember with pumpkins is that if the seeds are the same - shape and colour they will cross.
If you want to grow more than one variety of the same group you will need to hand pollinate, if you don't want to or can't the following season it will grow a cross, sometimes still edible but no good for seed saving. Just enjoy the harvest, observe how each plant performed and share this information, just DON'T save the seeds. .
To hand pollinate you need to start the day before identifying male & female flowers that are almost ready to open. They are starting to yellow but still shut tightly.
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| Female flowers. A tiny baby pumpkin or swelling is located between the stem and the flower. The female flower will be close to the vine and the stem will only be a couple of inches long. In the center is a multi segmented stigma which must be pollinated in order for the fruit to develop. the picture above shows a mature female with her flower open. You need to select one that is un-opened, seal it and come back to it the next day. |
and here are some more examples of female flowers
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| Female Watermelon flower (open) |
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| Female Cucumber flower |
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| Female Zucchini Flower |
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Male Flowers are on a stem that is fairly thin and shoots up several inches to a foot above the vine. The center stamen contains the pollen. Pollen is mature if it readily comes off the stamen and onto your finger. Again identify unopened flower, seal then come back to the next day. You really should select & isolate more than one male flower.
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some more male examples
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| Male Zucchini flower (closed good one for selection) |
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| Male Zucchini (open) |
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| Male Watermelon flower (open) |
Some Side by side comparisons
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| Zucchini (female top/ male bottom) |
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| Zucchini ideal for hand pollination selection flowers have not yet opened (female left/male right) |
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| Cucumber (female top/Male bottom) |
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| Watermelons (male top / female Bottom) |
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| Hubbard Squash flowers (female right/male left) |
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To make sure the pollen is mature. Touch the stamen with your finger and see if tiny yellow specks(the pollen) come off on your hand. Pull off the petals to expose the stamen which contains the pollen.
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Using the stamen itself gently rub the pollen onto the inside stigma of the female flower. Make sure to come in contact with all segments of the stigma.You really should try to use more than one male flower to get the right genetics.
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Hand pollination is now complete! |
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Now to avoid any further insect pollination of the female flower you must prevent insects from getting in there. A fleece bag, pair of stockings, a peg or some masking tape lightly tied over the female flower will do.
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If pollination did not occur, the baby pumpkin below the female flower will shrivel and die.
I also recommend that you watch this excellent demonstration
http://youtu.be/yrZ-VCI4Edc
Watermelons and cucumbers are essentially the same process but a little more fiddly because of smaller flowers this is another excellent demonstration
http;//youtu.be/q5yz4_mPSXM
