Today, March 22nd, 2011, I harvested a good quantity of vegetable spaghetti and full armful of small deep orange Kuri Squash, or as I know them after some time living in France, Potimarron.
The joy of harvesting such amazing looking veg has enthused me into making more of an effort than just popping some shop bought seedlings into a spare gap in the veggie garden. 2011/12 will be my year to learn more about growing squash and pumpkins, and hopefully see a better and more varied crop.
It’s no surprise to learn that the pumpkin is a member of the family that includes cucumber, zucchini, melon, pumpkin, squash and marrow. They are a member of the cucurbit family.
So what makes for a happy pumpkin?
From my research the following conditions should make for a healthy, productive pumpkin plant.
Site & Soil
An open, sunny spot with a fertile well drained soil. The traditional way of growing is to plants them on ridges or mounds of soil full of organic matter. However, the labour involved in preparing these manure rich mounds is not rewarded much more compared to planting into a well prepared flat spot.
The ideal soil pH range for a pumpkin plant is 5.5 – 7.5
I grew up watching the old folks simply chuck pumpkin seeds onto the compost heap, as the summer progressed the vines sprawled in every direction. I have read that the nutrients, namely the high levels of nitrogen, in a compost heap can lead to an overly leafy plant at the expense of fruit. I may give this a go at some point as a comparison of the effort to success ratio.
Planting the seeds
Here in Victoria, pumpkin seeds are best germinated in a propagator in mid to late spring and the young plant transplanted into it’s growing spot in late spring or early summer.
If you wait until early summer you can simply pop the seed directly in the prepared growing spot.
Successional planting is not really an issue with the pumpkin family as they produce a succession of fruit.
Taking care of the plant
When the seedlings have developed three or four leaves, which usually takes a coupe of weeks, they are ready to be planted into the veggie garden.
All members of the cucurbits family like to be kept warm in their early days in the ground, so a fleece or cloche is a good idea. As this part of Victoria can see a beautiful 28ºc day followed by a chilly 14ºc day, it is worth giving the plant a little protection.
Keeping the pumpkins fed is important but it is important to remember that too much nitrogen, as with the compost heap method of growing, can lead to a leafy plant with less fruit.
To feed cucurbits, I am going to try using a general organic fertiliser and dried chicken manure. My research has found a figure for the ideal nitrogen contents, that being 5%.
If the plot has been well manured in preparation of planting, the amount of feeding can be reduced.
Trailing pumpkins will not need as much watering as they root well as they grow. Too much watering may cause the roots and stem to rot.
Mulch is important, as always here in Australia where water is a scarce resource. Apply a good depth to help retain water and to keep the weeds at bay. The mulch will also help keep the pumpkins nice and clean too. Again, be mindful of the nitrogen in the mulch, else it’s back to having a leafy plant and few pumpkins.
Cucurbits have beautiful large flowers, the female is the flower with the miniature fruit forming at it’s base, whilst the make is simply a flower on a normal stem.
To aid the setting of fruit, especially when there are a lack of pollinating insects about, you can hand pollinate. Remove a male flower and take off all its petals so that the central stamen of the flower is fully exposed. Now insert this carefully into each of the female flowers, this transfers the pollen from the male to the female flower. It’s the same way a bee does it, just a little less romantic for the plant, especially the male!
You can train your pumpkin plant if you like things to be neat and tidy. I once saw a “baby bear” pumpkin staked into a spiral, which looked amazing. I have read that just letting the plant ramble can mean more fruit, so I reckon their is another comparative experiment to be had there.
If you want large pumpkins then it is best to remove fruit leaving one or two per stem. Otherwise you can just let the plant do it’s thing for lots of smaller fruits.
The sort of problems likely to be encountered when growing cucurbits are Powdery Mildew, stem and root rot, mosaic virus and of course there succulent stems are just too tempting for the slugs and snails.