Growing Squash from Sowing to Harvest

, written by Benedict Vanheems gb flag

Harvesting squash

Squashes and pumpkins are among the most thrilling vegetables you can grow. One minute the seedlings are tentatively pushing through and then, just a few weeks later, they’re great sprawling monsters with masses of leafy growth and plenty of fruits. I love the fact they’re so easy to grow too – as long as you can keep up with their insatiable appetite that is!

So let’s find out the very best way to grow them...

Summer Squash vs Winter Squash

Squash varieties come in all sorts of shapes, patterns and sizes, but fall into one of two categories: winter squash or summer squash. Winter squash are harvested in one go at the end of the growing season for a feast of fruits to enjoy over the winter months. They include favorites like butternut squash, spaghetti squash and the myriad of pumpkins. Summer squash are harvested throughout the summer and include, for example, zucchini, and patty pan and crookneck squashes.

Squashes are either trailing or bushy. Trailing squash can be left to sprawl over the soil surface or trained up trellis or wire mesh. For really big pumpkins though, it’s best to leave stems to sprawl. They will send down extra roots as they spread to take up even more of those valuable nutrients and moisture.

Summer squash is available in a wide range of shapes and sizes

Where to Grow Squash

Squash love a warm, sunny and sheltered spot – ideal conditions for good pollination and proper fruit development. The plants are hungry feeders and need a rich, fertile soil. Any soil can be improved by barrowing on lots of well-rotted compost or manure. Or create planting pockets by digging out a hole for each plant at least two weeks before sowing or planting. Fill the hole with a mixture of soil and compost or manure and top with a handful or organic fertilizer.

Smaller varieties of summer squash may also be grown in containers that are at least 18inches (45cm) wide.

Starting squash in pots under cover enables an earlier start to the season

How to Sow and Plant Squash

Sow squash directly where they are to grow after your last frost date. Sow two seeds to each position then thin the seedlings to leave the strongest. Pop a jar, cloche or cold frame over sowing areas to help speed up germination.

A more reliable alternative is to sow into pots under cover. Sow one seed per pot, about an inch (2cm) deep. Germinate in the warmth, at around 60-68°F (15-20°C). Sowings like this can be made up to a month before your last frost to give good-sized plants by planting out time. You may need to pot the quick-growing seedlings on into larger pots before it’s safe to move them outside.

Most garden stores and nurseries also sell ready-to-plant seedlings – handy if you only want to grow a few plants.

Set your plants out after all danger of frost has passed. Start to acclimatize them to outside conditions two weeks beforehand. Leave them out during the day for increasingly longer periods then, from the second week, overnight in a sheltered position. Plant trailing varieties up to five feet (1.5m) apart and bush types about three feet (90cm) apart. Thoroughly water plants into position to settle the soil around the rootball.

Squash has long vines that may need to be controled

Growing Squash

Keep plants well watered to encourage rapid growth. You can make watering easier by sinking six-inch (15cm) pots alongside plants. The pots will hold onto the water and deliver it through the drainage holes directly where it’s needed, at the roots. Mulch around plants with organic matter to help lock in valuable soil moisture and contribute additional nutrients.

Stems of especially vigorous varieties can be pegged down at regular intervals to keep them within their allotted space. Larger fruits, particularly pumpkins, should be lifted off the soil, for instance onto tiles, to stop them rotting as they develop.

Cure winter squash after harvesting to enable longer storing

Harvesting Squash

Harvest zucchini and summer squash as soon as they are the size you need. Pick often to encourage more fruits to follow. Winter squash and pumpkins are harvested in the fall before the first frosts, usually when the foliage has started to die back or become infected by powdery mildew.

Cut either side of the stem to leave a T-shaped stub. Avoid the temptation to use the stem as a handle as it could detach from the fruit and serve as an entry point to rot. Move fruits to a warm, dry and sunny spot to cure. Curing hardens the skin ready for storage. If it’s already turned cold and damp outside, cure fruits in a greenhouse or on a sunny windowsill. Winter squash and pumpkins will store for up to six months at room temperature.

And there you have it – growing squashes to be proud of is really very straightforward. As always, we welcome your experience of growing these rambunctious veggies – drop us a comment below to tell us what varieties you recommend and to share your tips for growing bigger, bolder fruits.

Bugs, Beneficial Insects and Plant Diseases

< All Guides

Garden Planning Apps

If you need help designing your vegetable garden, try our Vegetable Garden Planner.
Garden Planning Apps and Software

Vegetable Garden Pest Warnings

Want to Receive Alerts When Pests are Heading Your Way?

If you've seen any pests or beneficial insects in your garden in the past few days please report them to The Big Bug Hunt and help create a warning system to alert you when bugs are heading your way.

Show Comments


"I've heard that the heaviest crops of Crown Prince or Butternut squash will only happen if you pinch out the growing tips of the plant to promote side-shoots. Is this true? I don't want to damage the plant or reduce its yield. However, I usually only get 1-2 modest sized fruits per plant, but lots of leaf, so I'm trying to improve. If you think this is a good idea, when should I do this? "
KatyVic on Tuesday 7 May 2019
"I would advise that the best thing to do for a heavy crop is to allow the plants to sprawl over the ground. That way they can root into the soil whenever they please, drawing on more nutrients and water to produce more flowers and fruits. Good levels of soil moisture and sunshine are key to the biggest harvests, as is good soil fertility (a top-up around plants of organic much such as garden compost can help with this). I wouldn't worry about pinching out the growing tips, so long as you follow the above pointers. It's the growing conditions that will give you the best yields. "
Ben Vanheems on Monday 13 May 2019
"Thank you for all your advice and tips. I’ve planted 4 Seeds around 6 weeks ago. Now they have 3 or 4 leaves each but unfortunately 2 of them have just broken through windy weather. They aren’t completely cut off though, hanging by a small shred. Is there any way to save them?"
Sareh on Saturday 25 April 2020
"Those leaves are likely to shrivel and die. If the growing points and at least a couple of the young leaves are still intact, however, the plant is likely to be absolutely fine and to grow on. If the damaged leaves really are hanging on by a tiny shred, I'd just cut them off now so they aren't attracting disease/acting like a sail in the wind. Consider sheltering the young plants if you can. An upturned wire hanging basket with row cover/horticultural fleece thrown over the top will keep the wind off and offer a little extra warmth at night to really help plants get a strong start. You could improvise other shelter solutions of course."
Ben Vanheems on Monday 27 April 2020
"I have planted seeds and when the plants had 3-5 real leaves 9not the first 2 ones), I have put them in the ground. I did the same with zucchini. They are in the earth now for 2-3 weeks, Utd they don’t grow. I have put a foil tunnel over them and they have sun and water. Is there any tip you can give me how to help them grow or how long it is supposed to take them to grow? Thank you so much for your help and very good videos"
Amelie on Saturday 16 May 2020
"Hi Amelie. Sometimes squash and zucchini can 'sulk' for a few weeks after planting. They can go into a sort of shock, especially if planted quite early when the night temperatures are still fairly low or daytime temperatures aren't climbing that high. Some row cover can help to keep chilly winds off as they establish. You should find that they suddenly start to grow quickly - it just takes time."
Ben Vanheems on Sunday 17 May 2020
"I planted summer squash and the plants are small but are getting squash on them already! Should I prune flowers off to let plants mature more?"
Maxine on Tuesday 9 June 2020
"Hi Maxine. No, you're fine, just leave the plants as they are. Sometimes you find that the very first squashes on small plants don't amount to much until the plant has got in its stride and got a lot bigger. But either way, there's nothing for you to do except keep the plants well watered. "
Ben Vanheems on Tuesday 9 June 2020
"hi I planted squash plants and they are thriving (I think) I have one big yellow flower and lots of shoots. I have two plants per 50cm length and 7cm deep pots . should I move them so its one each per pot or is two OK in each pot. "
Erica on Thursday 16 July 2020
"I would move them so there is one per pot. Also, 7cm depth seems very shallow - they would need a deeper root zone than that if possible."
Ben Vanheems on Thursday 16 July 2020
"I have massive leaves and plants but can’t see any fruit coming. When will this happen? Thank you. "
Alison on Friday 7 August 2020
"Hi Alison. The flowers and first fruits should have already set by now. It could be that the ground you are growing in is very high in nitrogen, which would promote leafy growth over flower production. Or it may just be that your squash are late starters and will flower soon. I would perhaps start feeding them with a liquid feed that's high in potassium - one sold for tomatoes would be fine. This might encourage it to flower and set fruit."
Ben Vanheems on Monday 10 August 2020
"Hi, this is my first attempt at growing winter squashes from spaghetti, crown prince and acorn. Your information on curing them is invaluable. I have many squashes growing but most of my leaves have been overtaken by powdery mildew. With the UK weather raining it has been hard to treat these leaves. What should I do? Thanks,"
Shona on Thursday 27 August 2020
"Hi Shona. Powdery mildew does seem to be an inevitable part of growing squashes in wetter climates. The prevention and early treatments work to a certain extent, especially earlier on in summer, but as late summer tips into autumn mildew is, I'm afraid, inevitable and there's little that can be done to stop it. If your fruits are growing nicely I wouldn't worry, they should finish curing on the (sunshine!) even with the mildew."
Ben Vanheems on Tuesday 1 September 2020
"Hi, I wanted to let you know I found your article about growing squash from sowing to harvest very helpful. Thank you, Richard"
Richard on Thursday 10 September 2020
"I've never grown courgettes before and planted 3 plants, omg, they are coming thick and fast now I can't keep up with the amount of courgettes that we now have. Can they be frozen? Many Thanks"
RB on Thursday 17 September 2020
"Good on you RB - they're very prolific aren't they! Unfortunately courgettes don't freeze well as they turn to a mush on defrosting. You can either make them into a sauce with, say, tomatoes etc. and then freeze. Of perhaps try making courgette fritters, which may freeze okay. Search 'vegetable fritters' above for a fantastic recipe from Barbara. All those courgettes are a great problem to have it has to be said!"
Ben Vanheems on Friday 18 September 2020
ZANELE on Friday 16 October 2020
"Hi Zanelle. Assuming you are in autumn now, I'm afraid it is unlikely your squash will produce a useable fruit in time. They almost always get powdery mildew from early autumn, and once that happens any fruits that aren't already fully grown in size are highly unlikely to grow any further, though they will continue to cure (harden up/mature) on the plant. If the fruits are of a good size, despite such a late planting, then I would bring them under cover now to finish curing/hardening off indoors. "
Ben Vanheems on Monday 19 October 2020
"Hi. Thank you for the videos - this is great information as we are first time growers of spaghetti squash. We have very limited space so used a trellis bent in the middle to form an A-frame. We have lots of leaves from three plants but only four fruit in total. Should we have cut back the leaves as they seem to be hiding the flowers and would this stop the pollinators from doing their job? Also why do the flowers open at night and close during the day? Lastly would it be better to have a trellis up the wall for them?"
Mandy on Sunday 1 August 2021
"Hi Mandy. Don't remove the leaves - they are what is powering the plant. There shouldn't be a need to remove them. The pollinators should also be able to find their way into the flowers, no problem. I would perhaps check what you are feeding them - if flowers are failing to set it could be that they need more potash - a tomato feed would help with this. Generally it's best (if you have the space) to allow squash as much contact with the ground as possible, as this means stems can root into the soil as they trail along the ground, giving the plant more resources to draw on. A trellis up the wall might make the plants 'tidier' and fruits and flowers easier to see, but I don't think there'd be a huge difference in growth of the plant, as it's still lifted up off the ground. I'm not sure why the flwoers would be closed during the day - but perhaps this is a reaction to heat?"
Ben Vanheems on Monday 2 August 2021
"A neighbour gave me some seeds from a large orange pumpkin which he had bought and I planted and raised about 8 healthy plants from them but the fruit is completely different from a pumpkin and looks more like a marrow. The biggest one is about 18” long by 6” in diameter and green very much like a marrow (although I don’t believe it is a marrow as it didn’t start off as a courgette and the leaves are slightly different) do commercial growers cross fertilise the big orange pumpkins with something else and could this be the reason why it hasn’t come true? Also I have no idea what type of squash I now have as I can’t find it online at all, the nearest is the Cousa squash, is this a possibility? Many thanks. "
Jackie King on Thursday 28 July 2022
"Hi, I have planted Kabocha squash for the last 3 years, however, each plant would only produced 1 or 2 fruits, what did I do wrong? Everything seems to look right, it just stops setting fruit after the first one. Was it because the soil not rich enough? I do add compost tea every or every other week, I am very stumped by it. Thanks for your help. Kathy"
Kathy L on Sunday 14 August 2022
"Hi Ben, Enjoy your videos! Very helpful. I am growing a butternut squash from Northern Italy Zucca Butternut Rugosa in my garden in the Boston Massachusetts suburbs. Seeds from Franchi Sementi in Italy. Garden has limited sunshine but some extra 5-10-5 fertilizer and lots of water helps compensate for the limited conditions. Two comments: Vine management is very important if you want to be sure squashes ripen. Mid-August I cut away all of the tertiary vines and many of the secondary vines too. This removes a whopping 30% of the vines in my garden. Need to be brutal if you want the remaining vines and fruits to succeed. Secondly, I place a 12 x 12 inch Dri-Deck ( spelling?) pads under each of the squashes growing in my garden. Better than a hard floor tile that will kill the underlying grass. Dri-Deck pads are made in Florida USA and these pads can be reused year after year. I use -Dri-Deck panels in the bilge of my wooden boat to raise wet lines and anchor gear off the wooden planking. "
Bill Brett on Wednesday 14 September 2022

Add a Comment

Add your own thoughts on the subject of this article:
(If you have difficulty using this form, please use our Contact Form to send us your comment, along with the title of this article.)

(We won't display this on the website or use it for marketing)


(Please enter the code above to help prevent spam on this article)

By clicking 'Add Comment' you agree to our Terms and Conditions