You probably think you already know how to grow a zucchini plant but if you live in North America ... you might not. Here's a way of growing zucchini to make your plants live longer, take up less space and produce more.
Zucchini is touted as one of the easiest and most prolific vegetables you can grow in a home garden. And that's mainly true.
Planting zucchini can be done by any fool. You stick a seed in the ground, go inside to watch television for a few weeks, come back outside and BOOM you have a zucchini plant.
But there are a few things about growing zucchini that you probably don't know. Even I, who has a 40' x 40' vegetable garden, who is a contributing writer for The Old Farmer's Almanac, who grows almost all of her own vegetables, didn't know these things until a few years ago.
1. Zucchini need to be pruned and staked. For real. Like you prune a tomato.
2. Zucchini can be planted VERY close together. 1 per square foot.
3. Powdery Mildew CAN be halted.
The most interesting fact about zucchini is they can do complex math equations.
No they can't. We're very alike zucchini and I.
If you're looking for a really rewarding challenge that's a little more mysterious than zucchini take a look at my expert tips on how YOU can grow luffa sponges at home.
Table of Contents
Growing zucchini
- Zucchini are a summer squash so these tips and techniques can be applied to any other summer squash like yellow, crookneck or patty pan.
- Seeds or seedlings can be planted into warm soil at the start of summer (typically the end of May).
- Zucchini fruit develop around 50 days after planting. Once the fruit form, zucchini grow very quickly - especially if it's hot out and they get plenty of water.
- Zucchini don't need a lot of soil amendments. Add 2-3 inches of mature compost on top of your planting site and you'll be rewarded with enough zucchini to fill a clown car.
When to plant Zucchini
- Zucchini are heat loving plants so wait until your soil temperature is above 65℉ (18ºC) to plant out seeds or seedlings.
- You can plant 2 weeks earlier if you lay plastic mulch on your planting area which will increase the temperature of the soil below by 10 degrees. Garden centres sell black plastic mulch, which is often biodegradable but any black or clear plastic will work. Get biodegradable black mulch here.
- Planting 2 weeks earlier also means you will be harvesting 2 weeks earlier!
- If you're starting seeds indoors, plant them 3 weeks before your last frost date.*
Because zucchini grow so quickly and don't always transplant well there's really no need to start them inside. They usually do better when direct sown under plastic mulch. Just cut an X into the thermal plastic and push the seed down into the soil through it.
Where to plant
- Zucchini needs to be planted in an area that gets 6-8 hours of sun per day.
- Plant near companion plants like beans and peas (which fix nitrogen into the soil).
- Surround zucchini with pollinating flowers like borage, catmint, dill or dahlias to attract pollinators to that area of the garden. (zucchini need pollinators to hop from their male to their female flowers in order to produce fruit)
How to plant zucchini
Supplies
- Zucchini seeds or seedlings
- Large pot or 1' square of soil
- Water
Instructions
STEP 1 - Make sure your garden is weed free and rake it smooth.
STEP 2 - Apply a 2-3" layer of compost on top of the soil and rake smooth. If you're laying down plastic mulch to speed up your planting and harvest date, now is the time to do it.
STEP 3 - When the soil registers 65℉, plant seeds to a depth of 1" which is about the distance from the tip of your index finger to your first knuckle. For seedlings, plant them so the soil line of the seedling matches the soil line of the garden. Then push the seedling down a little to firm it and add more soil to fill the space if needed.
STEP 3 - Cover the seed with soil and water well. Make sure the soil doesn't dry out at all until you see the seeds sprout.
STEP 4 - Maintain moisture for the rest of the summer with at least 1" of water a week. Zucchini LOVES water. And don't worry about getting water on the leaves. Water doesn't exacerbate or cause powdery mildew. In fact, water helps wash it off of the plant. Powdery mildew is triggered by dry conditions - not wet.
THESE are the two tricks to growing zucchini better than anyone else: staking & pruning.
How to stake zucchini
Growing zucchini vertically might not be your first thought but it's exactly what you should do.
North American gardeners haven't really adopted this technique yet but it's common in Europe.
STAKING
- Drive a 4-5' stake into the ground before planting, so you don't damage the roots. I use lightweight coated metal stakes.
- Plant your seed or seedling right next to the stake so as it grows you can tie the stem to the stake.
You may not have noticed it before, but a zucchini plant only has one stem. That stem is just usually sprawled and dirty on the ground covered in decaying leaves. So you can't get a good look at it.
But trust me. Zucchini have one stem, that can be staked just like a tomato.
The earlier you do it the easier it is though.
Above you can see a zucchini plant that's only been staked and tied once, earlier in the season with the rest of the growth just flopped over. The leaves are being eaten by bugs, there's no air circulation and the lower leaves near the soil are getting powdery mildew.
Here's the same zucchini plant after staking it properly and removing all the lower leaves.
Just like tomatoes, zucchini benefit hugely from pruning. They'll be susceptible to less disease, have a more open formation that allows easier access for bees to pollinate and they'll take up less space.
How to prune zucchini
Why prune?
- The developing zucchini gain all their energy from ONLY the leaves growing above them. The leaves below, are just taking energy away from the rest of the plant.
- Pruning away diseased and damaged leaves helps prevent and slow powdery mildew by creating greater air circulation.
- Pruning away the larger, lower leaves that aren't contributing to the plant means you can plant more zucchini in a smaller space.
- The flowers are easier for bees and butterflies to access.
PRUNING
- Locate the lowest growing zucchini on the plant.
- Cut off all of the leaves growing from the stem below that zucchini. Cut right close to the stem.
- As the plant grows continue cutting off any leaves that are below the lowest growing fruit.
Fun Fact
Zucchini leaf stems are hollow UNTIL they get to the stem of the plant. There they turn solid again. Prune your zucchini leaves right up to the stem of the plant so you don't have any of the hollow stem left.
- Hollow stem portions can harbour disease and bugs so make sure you get right close to the plant stem when removing the leaves.
Pre staking & pruning
Post staking & pruning
See the difference from the left photograph and the right one?
Spacing Zucchini
Plant zucchini 1' apart. Rows should be spaced at 1.5' apart.
A lot of guides tell you to place zucchini plants at least 24" apart. You don't need that much room between them.
If you're staking & pruning them this is all the room they need.
Unpruned zucchini
Pruned zucchini
SOME MORE GOOD VEGETABLE TIPS FOR YOU
SAVE Your Zucchini and Squash from Squash Vine Borer
My Leek Growing Technique - Based on Eliot Coleman's
Make Paper Pots with a Wine Bottle
Make a Soil Grader for Levelling Your Garden from a Wood Pallet.
Disease
Powdery Mildew
- It's the kiss of death for zucchini plants, but luckily it's a long, slow, torturous death.
- Most zucchini plants seem to be able to withstand powdery mildew for quite a long time - months even.
- To help prevent powdery mildew, stake and prune your zucchini like I've shown you.
- If you notice powdery mildew has made its way onto your plants you can spray with this homemade Powdery Mildew spray for zucchini. It's just vinegar and water but it works.
Pests
The number 1 killer of zucchini plants are squash vine borers. These maggoty stem eating bits of grossness can kill a plant before you even realize it's sick.
Squash vine borers bore their way into the stem of the zucchini along the soil line and then proceed to eat the entire plant from the inside out.
There's usually only one vine borer per stem, so all you have to do is check your stems for signs of it at the end of June and into the summer.
I have a whole post on how to remove squash vine borers from your zucchini, winter squash, pumpkins and other gourds.
How to Grow Zucchini Plants
How to grow zucchini plants the right way! And I bet it's different than how you're doing it now.
Materials
- 4-6' long stakes
- twine
Tools
- scissors or knife
Instructions
Plant your zucchini 1.5" apart. They aren't going to need all kinds of room to grow and sprawl anymore because you're growing them UP.
Plant a stake right next to the main stem of the zucchini plant.
Using string or twine tie the plant's stem to the stake so it grows upright.
Remove all those huge leaves that are growing at the base of the plant (only the leaves below any developing fruit)
Monitor the plant once a week to see if you need to tie it to the stem again as it grows.
Notes
Zucchini should be grown basically like tomatoes! Stake them and remove older leaves that aren't doing anything productive for the plant other than making it vulnerable to disease.
Staking is easiest if you do it when the plant is first put in the ground, but you can wrangle an older plant into submission as well.
Cut your leaves off as close to the stem of the plant as you can.
If you see signs of powdery mildew developing you can wash the plant. Yes. Wash it with water. Powdery mildew HATES water and thrives in dry, hot conditions.
Powdery Mildew can also be controlled (not cured) with this simple spray recipe:
4 cups of water + ½ Tablespoon of Vinegar.
Spray the top and bottom of the leaves once a week.
Zucchini can be picked at any time. All sizes are edible. Yes. Even the big ones. Larger zucchini will need their seeds removed.
Absolutely. Zucchini are perfect for pots, especially if you use this staking and pruning method to control their size.
Zucchini season runs from June to August. The plant begins to produce fruit around 50 days after planting. To extend your season, plant first at the end of May and then again at the end of June. This way if you lose plants to disease or pests, you'll have another crop on the way.
If your zucchini grow to about the size of your pinkie finger, and then rot and fall off you have a pollination problem.
This is caused by the female flower (which has the fruit) not being pollinated by the male flower. You either need to attract more pollinating insects to your garden OR I can show you how to hand pollinate.
Apply what you've learned here and you'll have your biggest zucchini crop ever.
You might be wondering why would you want them to produce even more? Zucchini are already insanely productive. Well, because of the obvious. They’re fun to throw through people’s open car windows during zucchini season.
Zucchini may not be able to do complex mathematical equations but they can add up like nobody's business.
→Follow me on Instagram where I often make a fool of myself←
Love your gardening tips! We staked our zucchini plants this year, and while the plants look good, we have noticed that every zucchini that grows pointing down, does well, while every zucchini that grows pointing up turns yellow and rots when it reaches 2-3 inches. I have had to remove quite a few. My husband pointed this out, and I chuckled, but sure enough, it is true. Any thoughts as to what is going on and how we can “cure” the problem?
Hmm. It's definitely (I think, lol) something to do with pollination. It could be that the ones pointing up aren't as enticing to the bees?? ~ karen!
Karen, thank you for your help! We have never had this problem before, and I guess I needed a biology lesson on zucchini. One morning I watched as a couple of bees visited the male flowers but totally ignored the females, which happened to be pointing up. Weird, right? But with some “help”, we now have zucchini growing all over. I would include pictures of our “zucchini babies” if I could. Thanks so much!!!
Excellent! ~ karen
This is good information. I've had problems of fruit drop, also, but we had so many bees. Never did I think the females were just too excited - LOL.
What did you do to attract the bees?
Hi, for years we've been growing strains of bush Zucchini (typically the heirloom Black Beauty). Any tips for preventing powdery mildew as staking isn't an option)
Yes, you can spray it off with water occasionally and use this spray https://www.theartofdoingstuff.com/dealing-powdery-mildew/ ~ karen!
My Zucchini plant has a lot of female flowers begining to form but no male flowers in sight. What happens if a male flower doesn't grow at the same time a female flower is open? Thanks!
Hi Jeanna! They will. :) Just give the plant time and it will start producing both flowers and the beneficial insects will take care of the rest. (but remember you can always pollinate yourself) ~ karen!
My squash this year are smaller and already have fruit (squash) growing on them all. Is it ok to remove all the fruit so I can hopefully grow some leaves or should I just let em grow. They’re small small lol but the fruit is as plentiful as ever a squash has
Thank you for any advice and your time. This article is amazing!
Hi Karen-
I have a question for you. My zucchini flowers often 'fall' off when they are a day or two old. And where they used to be is a mark on the plant that looks like somebody cut the flower off.
I assume this may be a pest of some sort? Any ideas on how/what I can do to prevent this from happening? I have never had any success with growing zucchini because of this.
Hi Mary! Hmm. I'm not sure. My first guess is that they're actually falling off when they should. The female flowers are only open one day. So your actual probably might be pollination! When you grow them this year, every time you see a female flower open hand pollinate it. See if that helps your situation. ~ karen!
Love this article! Quick question: can zucchini be grown up a string trellis similar to your method for tomatoes?
Hello Malia... I'm just another reader but wanted to encourage you to do the string trellis for your zucchini. I put in my first garden this year and after a lot of reading I planted my zucchini on a string trellis along with several other garden vegetables and thus far, it's a success. Good luck & happy gardening!
Hi Lynn! I'm right there with you, first year with a vegetable garden and set up a string trellis for the tomatoes, cucumbers and zucchini. Bit of a risk with the zucchini perhaps, but what's the worst that can happen? Thanks for much for your kind note, very thoughtful of you.
I agree with Lynn. I too used the string trellis method for my squash and zucchini this year. I use this method every year for my tomatoes and find it easier than staking. I already have a few yellow squash fruit growing! I have never been successful with squash because of the dang vine boreres but I'm very hopeful this year. Thanks for all your tips Karen!
staking the zucchini information has been very helpful. I had not done this before now I will. thank you
Good luck Claudine! I think you'll like the method. ~ karen!
If you have an overabundance of any garden produce please consider sharing with your local food pantry.
Great post! I have never had luck with the easiest veggie plant in the world. We have too many overgrown trees in neighboring yards so the sunlight in my yard is iffy. I’m going to try this method in a big pot on my deck. Has to be better than what I’ve tried in the past. Now, I just hope that the blossoms develop into zucc! They were always falling off before producing before. 🤞
K,
Are you sure that the baby zucchini rotting is a pollination issue?
I believe the baby zucchini die off because the plant isn't getting enough calcium in the soil. You can either go full organic and add clam shells, egg shells or other supplement... or mix up a nice tasty gallon of water with a 8-10 Tums antacids. Pour that on as you would regular water, at the base of the plant, and it should resolve the rotting dead baby zukes issue. At least it did for my gardening partner and me.
You might be referring to blossom end rot which happens at a later stage. ~ karen!
Okey doke... good to know. Less guilt for us.
Now about that "release the doves" email... WTH?
Hi Karen,
We want to try the zucchini staking method. We live in California, so have great weather to grow them but we haven’t grown zucchini in a few years because the zucchini were always eaten by rats or squirrels☹️ This year we’re going to try using a wire screen cover given to us by a friend. It’s roughly 4 feet square and 3 feet high. We plan to put 2 plants in it. So we will put a stake next to each plant but what should we do when the main stalk reaches the top? Could we train it horizontally at that point? What do you suggest?
Hi Michele. I'm new here but have dealt with your issues in California. For the squirrels, I use a trap system and bait it with peanuts or sunflower seeds. Check each morning to see if you have trapped one. If so, then drive the marauder at least 2 miles away and release it. For the rats, you can use one of the newer rat trap devices or get a cat. Stay away from poisons for reasons you may already know. Not safe. Hope this helps.
Great article on zucchini! Will staking and pruning work on yellow crooked neck summer squash??
Oh, Thank you so much Karen for this blog post. I have never staked my squash, but i will from this time forward. In fact I am trying many different things to my garden this year, maybe here in Texas I can get in a second crop and stake them. Thank you again
So, the number one killer of squash here on the southern plains (Oklahoma) is squash bugs. They can kill a fully grown adult plant that has produced squash for days in one evening. They live in the damn soil, and are the bane of all existence here. Any ideas?
Nasturtium plants have repelled my squash bug problem every time!
Yep, heard the same thing...those creepy bugs give me the willies. Will be trying Nasturtium plants this year along with my daily diligence of vacuuming them off! :)
Thank you, for your article. It's very informative. I am going to try this, with my zucchini's.
As for the squash bug problem.
I use a small ag sprayer, with about 1 Tbsp Dawn dishsoap (the blue kind) & fill it with water.
I spray it onto the plants & onto those nasty squash bugs.
It kills them, just like stink bugs (which squash bugs, are related to).
I hope, this helps you.
Here’s what I have done this year and seems to be working. Stake as mentioned in the article. Mix 2 Tbsp Neem oil and 1 Tbsp dish soap in a 1 gallon water sprayer. First I inspect each leaf underneath for the reddish copper eggs and remove. I’ve tried different ways; smash against the leaf & remove, use a sharp knife and cut them out, use masking tape and remove (I’ve not done this yet cut saw it on You tube). Be sure to dispose. I use a plastic container with a top to put them in. Then, spray the leaves from top, underneath and the stems and ground below. You need to inspect daily or rid the eggs before hatching the disgusting squash bugs. I am going to spray every 2 or 3 days as long as I still them. I started last Friday and it is Monday. They look great. I’ve harvested 2 8” zucs so far. Looking forward to a great harvest. I hope that helps.
Thanks! I just stuck my shovel in just to loosen the soil so I could pull up one of two I planted. They were almost 2 feet apart and way too close OR SO I THOUGHT. But I didn't pull it up, at the last minute I thought what can it hurt, I'll just keep the lower leaves trimmed back for more air here in hot, humid Florida. Well I never did pull it up as it was growing so well and now I'll just go stick posts next to both of them and prune. Thank you so much. Zucchini should be easy but for some reason, mine never work - armadillos, rabbits, insects, mildew, deer, cats.
Sounds like me when I grow beets, lol. Everything gets to them before I do. ~ karen!
Great article, but the last thing I want my zucchini plants to do is produce more. My neighbors already hate me.
Haha. Too funny! Last year we shredded some and spiralizing some to make noodle and froze it to enjoy in the winter when we weren’t tired of it!
is the zucchini staking good for cucumbers as well? thanks!
Last summer I grew my cukes in pots and let them sprawl up a section of metal fencing we suspended out from the deck railing. The cukes grew better because they actually fell low the leaves and were easily p icked from underneath the support. Keeps them cleaner, better air circulation.
thanks for advice!
Hi Kirsten. Cucumbers grow on a much longer, much thinner stem. The best way to keep cucumbers under control is to wind them up a string (string training). ~ karen!
A great article! I am ready to try this method. Thank you so much.
You're welcome! It really works great. Do yourself a favour and get those stakes in right away and keep tying them up as they grow. It just makes life easier. :) ~ karen!
“You’ll be awarded with enough zucchini to fill a clown car.” 😂😂🤣🤣🤣 lol!!!!!
Hi Karen!
I have a horrendous maggot story where there were hundreds of them (I swear) in my breezeway on the floor from a plate of can cat food my husband carelessly threw in a wastebasket. I didn't know this at the time.... So anyway I got up for work very early in the dark and headed to the breezeway to fill my cats dry food bowls and stepped all over them!!!! :( In between scooping up with broom and dustpan and mopping floors at 5 AM I found out that maggots smell....BAD!
Needless to say my husband never did that again!!
So anyway, I see your corn in a photo. One of my biggest problems is my corn falling over and getting trashed from windy thunderstorms.
Any ideas??
Thank you!!