No doubt my non-South African readers are scratching their head and asking what the hell is a gem squash and why do we need a whole post dedicated to them. Well, let me tell you – it is probably the thing that South Africans abroad crave the most, and one of the more frustratingly unobtainable. In fact, when my half-sister emigrated to France in the 1970’s she missed gem squash so much that she smuggled a packet of seeds into France with her and planted them in her garden there, just so that she could have a steady supply. Biltong is now made in most countries where Saffers congregate; to get boerewors, all you need is a good spice blend and a tame butcher to make it for you; and Rooibos tea has practically conquered the world. But gem squashes seem to be the holy grail for expat South Africans, judging by the deluge of comments that have followed my two previous posts on them.
So what is this mythical vegetable of which I speak? Gem squash (similar – possibly genetically identical – to rolet squash, 8-ball squash or courgettes ronde) originated in Central America and belong to the botanical genus Cucurbita, which includes most gourd and melons and can be subdivided into Cucurbita maxima (Hubbard squash and buttercup squash); Cucurbita mixta (cushaw squash); Cucurbita moschata (butternut squash); and Cucurbita pepo to which gem squashes belong, together with most pumpkins, acorn squash, marrows and cucumbers. More generally, though, squashes are categorised as summer or winter squash, which has little to do with their time of availability, but rather their time of harvesting and degree of maturity at harvesting. Winter squashes are generally left on thne vine until the end of summer before they are harvested, making their skin hard and tough, which makes it possible to store them for consumption at a later date. Summer squashes, on the other hand, are picked when they are still young and tender. They need little or no cooking (e.g. zucchini) but don’t keep as well as winter squashes. Included in this family would also be the wonderful pattypan squash (also called scallop squash) which was a staple food back home but not something I’ve seen generally available in UK supermarkets 🙁
Gem squash falls into the summer squash category, but I must say that the gem squashes vary greatly in terms of how thick their skin is – a function of how early or late they were picked. The ones we get in we get in South Africa (often sold by the roadside in 5 or 10kg bags) tend generally to be pretty thick-skinned and once cooked, hold their shape to form their own little biodegradable bowl. The ones sold in the UK, however, live up to their summer squash description and the skin is often soft enough to eat once cooked. In South Africa we also get baby gems – approximately the size of ping-pong balls and cooked in the blink of an eye. You just eat the whole thing, no mess, no fuss – and they are SO sweet and delicious.
So if the supermarkets don’t sell them, the only way forward is to grow your own. Judging by the number of queries I have received, lots of expats want to know how to grow gem squash, so here is a little guide, collated from various websites and reader comments.
HOW TO GROW GEM SQUASH
- Choose your location wisely as gem squash need a lot of space to grow. They send out long vines and will take over your vegetable patch if you allow them to. Some growers construct A-frame trellises for the vines to trail on which keeps the plants off the rest of your garden, and the fruit off the ground (where they might rot).
- They are not frost tolerant and require temperatures of between 18C to 27C for optimum growth. The frost free growing season in the northern hemisphere is roughly between April and November.
- Sow your gem squash in the sunniest spot in your garden (particularly in colder countries), in rich, well-drained soil. Add some compost to the soil before sowing for best results and sow the seeds in rows, 2cm deep and 1m apart. Keep the soil moist, but not waterlogged as this will cause the seeds to rot. Mulching is not necessary as the large leaves of the squash plant provide similar protection from moisture loss.
- A handy hint from reader UK Stephen Brosin is to “dig the planting hole far too big, place a handful or two of 3-4 day-old grass clippings in the hole, add some compost and some slow-release fertilizer and then plant your seedlings on top. If you have a compost heap, grow your gems on the heap!”
- Gem squashes have similar growing requirements to cucumbers and prefer organic liquid feeds high in potassium.
HOW TO HARVEST GEM SQUASH
Harvest takes place in early Autumn. If you are planning to keep the squashes for a while, the fruit is ripe and ready to be picked when the skin is too hard to pierce with your fingernails. However, it is unlikely that you will get to this stage in the cool Northern Hemisphere (see below for the problem of powdery mildew), so probably better pick to pick them as soon as they approach the size of tennis balls (or even earlier), regardless of how soft the skin is. If growing Rolet F1 squash, UK reader Stephen Brosin says: “Rolet F1 , if left just a bit too long, gives a very fibrous squash not at all like a pukka gem. When picked young, however, the Rolet F1 makes a very passable substitute and is most enjoyable”.
GEM SQUASH PESTS
The one problem that WILL arise when growing gem squash (or butternuts, courgettes and cucumbers) in cool climates is powdery mildew, a fungus which strikes later in the growing season. The growing season simply is not long enough and the onset of the cooler weather stresses the plants which makes them vulnerable to mildew for which there is no cure. To try and fight the onset of powdery mildew, readers have sent the following tips:
- Grow the plants in full sun.
- Take care not to wet the leaves when watering – rather make sure you water the soil directly, not the plant.
- If possible, construct a temporary greenhouse over the plants with wooden battens and clear polythene sheeting, to keep water and cold winds off the plants.
- Reader Ed says: “Gardeners and farmers in the USA use a fungicide containing myclobutanil for it. In the UK it is only approved for ornamental plants and fruit trees but I figured if it’s good enough for American gardeners I should give it a go!”
- Some gardeners have experienced success by spraying affected leaves with a mixture of 1 part skim or low-fat milk to 9 parts water (a 10% solution of milk, in other words). Others say that 1 tsp. (approx. 5 mL) of baking powder (sodium bicarbonate) dissolved in 1 quart (just under a liter) and sprayed on the leaves will knock it back. Although these may slow the powdery miildew, they will not kill it, but at least the plant may survive long enough to mature your crop.
- Cut off badly affected leaves to encourage air flow and light to all parts of the plant.
HOW TO HARVEST GEM SQUASH SEEDS
If you are lucky enough to have grown a mature crop of gem squash, then you can harvest seeds from the fruit before cooking and grow more next year. Reader keith Meintjies has this advice: “To harvest the seeds: Leave the squash on the vine until the vines die back, or buy mature squash that are not all green but have a touch of yellow/orange colour on their skin. Halve the squash, and scoop out the seeds before cooking. Rinse the seeds to remove them from the squash strands. Dry the seeds on paper towel at room temperature for a week or so, then store them in a resealable plastic bag or old plastic 35mm film cannister.”
GEM SQUASH NUTRITIONAL VALUE
The gem squash is low in calories and contains useful amounts of vitamin A and C, as well as iron, folate, potassium and niacin.
WHERE TO BUY GEM SQUASH & GEM SQUASH SEEDS
Depending on where you live, it may be possible to buy gem squash fruit, seedlings or seeds. Here is a list of the places I have found and that readers have told me about to buy gem squash, Rolet squash, courgettes ronde, 8-ball squash or Tondo Chiaro di Nizza – if you know of others, please e-mail me or leave a comment and I will add them.
In the UK:
W Robinson & Sons (as Little Gem squash seeds)
Chiltern Seeds (as Tondo Chiaro di Nizza seeds)
Mammoth Onion (as Little Gem squash seeds)
Moles Seeds (as Rolet squash seeds)
More Veg (as Rolet squash seeds)
Nicky’s Nursery (as Rolet squash seeds)
Vegetable Plants Direct (as Rolet squash plants)
The fruit themselves are available from Waitrose, Borough Market in London (and probably other farmers’ markets), and sometimes the large branches of Tesco & Sainsbury’s. They also crop up fairly often in the Abel & Cole and Riverford organic boxes.
http://www.thesouthafricanshop.com.au (as fruit, when in season)
Shop 7 & 8 Upper Level Templestowe Village
112 James Street
Hahndorf Vegetable Market near Adelaide (as fruit, when in season)
Southern Harvest (as gem squash seeds)
Satooz website (as gem squash seeds or fruit)
Springbok Foods (as gem squash fruit, Nov to Apr)
Diggers Club (as gem squash seeds)
www.kingsseeds.co.nz (will deliver to the UK)
The Farm Store Kerikeri
8 Hall Rd Kerikeri
ph 09 4077607
Gem Squash seedlings. $2.50 pot of three
In the USA:
Park Seeds (as similar Eight Ball F1 squash)
Baker Creek Heirloom Seeds (as similar Tondo Scuro di Piacenza)
HOW TO COOK GEM SQUASH – GEM SQUASH RECIPES
OK, I hear you ask, that’s all fine and well, but what do you do with a gem squash?
- You can peel and quarter the gems, scoop out the seeds and roast with olive oil. But personally, if I can avoid peeling a squash then I will!
- You can do what my dad still does to this day: slice the squash in half around its equator, boil (or steam or microwave) until the flesh is soft enough to scoop out the seeds easily. Then add a knob of butter in each hollow, mash the flesh inside the skin and season with cinnamon sugar.
- Alternatively, if the idea of sweet vegetables is off-putting to you, try the same idea but with sea salt, black pepper and thyme. I have even mashed mine up with a balsamic dressing which worked well. For something creamier, try my Rozenhof creamy gem squash recipe.
- Prepare and steam the squashes as above, then fill each hollow with a spoonful of vegetables of your choice mixed with pesto and serve (also ideal as a vegan meal).
- You can make gem squash stuffed with a beef mince and tomato ragu – hubby’s favourite.
- You can make gem squash stuffed with a spicy creamed sweetcorn mixture and topped with cheese – my favourite way of eating them!
For more gem squash recipe inspiration, have a look at my dedicated Pinterest gem squash recipe board: