Quick Take: Pruning your squash and zucchini plants is the single most underrated thing you can do for your warm-season garden. I fit four squash plants into a 4x4 raised bed using this exact method, and I doubled my harvest by doing it.

By Nicole Johnsey Burke: Founder of Gardenary and Author of Kitchen Garden Revival

Three Reasons to Prune Squash Leaves

Pruning your squash and zucchini leaves regularly allows you to:

• Maximize fruit production
• Deter squash vine borers
• Grow more plants around the squash plant

Let's look at each of these in turn. Then, I'll tell you how to prune the leaves of your squash plants so you can reap these rewards at home.

Pruning Squash Plant Leaves Leads to More Fruit

Pruning the leaves is an easy way to encourage a fruiting plant to produce more of the good stuff. When you remove extra foliage, you free up some of the plant's energy to put toward producing more flowers and fruit. You're also telling the plant to direct its resources like water and nutrients to the remaining parts.

I ran a little experiment in my garden between four squash plants (highly scientific, I know). The plant that I pruned the least had the least amount of squash blossoms and little fruits forming. It was only supporting about five little squashes, when the most heavily pruned plant had ten fruits in production.

At the end of the day, it's simple: If you take off more leaves, you get more fruit.

Pruning Squash Leaves Deters Squash Vine Borers

Squash vine borers are particularly gnarly as far as pests go, and in my experience, there is no way to fully prevent them. Keeping the soil area clean around your squash plants instead of giving these little bugs a place to hide under leaf debris, mulch, or straw is one way to protect your plants. Another way is by pruning the foliage that's closest to the ground.

Pruning is an easy way to remove potential habitats and easy food sources for pests. With squash as with any other plant in the kitchen garden, it's best to remove any leaves or stems that are touching the soil. Think of these stems as pest highways, and it's your job to put up roadblocks.

Pruning Squash Plants Frees Up Space in Your Raised Beds

How do I manage to fit four squash plants, four pepper plants, three tomato plants, one cucumber plant, and loads of herbs and flowers in just 16 square feet of gardening space? Pruning.

My goal is to grow as much squash as possible without turning over an entire raised bed to these plants. I can do this by planting my squash plants on the edge of the bed so that some of the leaves and fruits will hang over the side. Pruning then allows me to encourage the plants to grow vertically rather than horizontally. If left to their own devices, yellow squash and zucchini plants spread wide; they'll even take up the entirety of a bed if you let them. Just look at the zucchini plant in the picture below.

After a couple weeks of being pruned, squash plants will produce flowers near the center of the plant instead of the outside, which is exactly what we want to happen. This is how you can grow more in a much smaller space.

How to Prune Squash Leaves

You'll begin pruning your squash plants as soon as you see the first flowers form.

Once a week, head outside with a clean pair of needlenose pruners. (It's a good idea to regularly rub your garden tools down with some rubbing alcohol to prevent spreading disease from one plant to another.)

Start at the base of each plant and work your way up, looking for non-flowering stems. It should be pretty easy to tell which stems are just forming leaves and which ones are forming squash blossoms. The ones that will only form leaves are thicker cylinders with large leaves at the end. These cylinders are actually hollow.

The flowering stems, in contrast, will be much thinner and won't extend very far from the interior of the plant. They'll end in a bloom that may have a little bulge right behind it if it's a female flower that will turn into fruit.

Your goal is to remove two or three non-flowering stems each week.

Prune each stem very carefully and as close to the main stem as possible. Like I said, the stems of your squash plant are hollow, so you don't want to leave a lot of stem behind—that would only promote pests and disease. Keep the rest of the stems so they can keep on growing.

Below, you can see the hollow remnant of a pruned stem. (Plus lots of little buds forming and fruits growing!)

Frequently Asked Questions About Pruning Summer Squash

When should I start pruning my squash plants?

Begin pruning as soon as you see the first flowers form on your squash plant. Before that point, the plant needs all of its leaves to establish itself. Once flowering starts, removing non-flowering stems every week will redirect the plant's energy toward fruit production.

How do I know which squash stems to prune?

Look for thick, hollow stems that end in large leaves only — these are non-flowering stems and are safe to remove. Flowering stems are thinner, grow close to the center of the plant, and end in a blossom, sometimes with a small bulge behind it indicating a female flower. Always keep the flowering stems.

How much of a squash plant can I prune at once?

Remove no more than two to three non-flowering stems per week. Removing too much at once stresses the plant. Consistent weekly pruning is far more effective than one heavy pruning session.

Does pruning squash really help with squash vine borers?

Yes. Removing leaves and stems that rest on or near the soil eliminates the hiding spots and entry points that squash vine borers rely on. It won't guarantee you'll never see them, but it significantly reduces the risk and makes your plants less attractive targets.

Can I really grow squash in a small raised bed?

Absolutely. Nicole grows four squash plants in a single 4x4 raised bed by planting them at the edges so leaves and fruits hang over the sides, and pruning weekly to encourage vertical rather than horizontal growth. The key is consistent pruning from the moment the first flowers appear.

What tools do I need to prune squash plants?

A clean pair of needle-nose pruners is ideal for getting close to the main stem without damaging it. Wipe your pruners down with rubbing alcohol between plants to avoid spreading disease. Make your cuts as close to the main stem as possible — squash stems are hollow and a long stub left behind invites pests and disease.