How to Grow Zucchini

Days to germination: 4 to 8 days
Days to harvest: 60 days
Light requirements: Full sun
Water requirements: Frequent regular watering
Soil: Well fertilized with good drainage
Container: suitable for some bush varieties

Introduction

Like tomatoes, zucchini is another popular favorite with home gardeners. Healthy zucchini vines can produce a huge harvest each year, and many people end up trying to give away their extra zucchini because they have so much of it. It’s often called “summer squash” as well.

Most zucchini varieties grow as a spreading vine, which can take up a lot of space. You can conserve space by training the vines up a trellis, and there are also some bush varieties. Most zucchini are long and tube-shaped but there are some round varieties too.

Zucchini is a very flexible vegetable that can be used either raw or cooked. You can even use zucchini in baked goods, like bread or muffins. They are very high in vitamins A and C, manganese and fiber.

Starting from Seed

Zucchini plants can be started from seed either indoors, or directly in the garden. You should start your zucchini seedlings indoors about 2 weeks before your last frost date. Zucchini grow very long roots, so start your seeds in small pots that are several inches deep and be very careful not to break the roots when you transplant. The seeds should be planted about 1 inch below the surface of your potting soil.

Because you can get 16 or more fruits per vine, you really don’t need that many plants. Three or four is usually enough for a family. If you get too over-zealous, you will almost certainly be overrun with zucchini at harvest time.

Alternatively, you can sow the seeds directly outdoors after the threat of frost is past and the soil has warmed up. See the transplanting section for more on planting right into the garden.

Transplanting

You should plant your zucchini in the sunniest part of the garden, and they love the heat.

If you are planting your seeds directly into the garden, plant the seeds about 1 inch deep, with about 6 seeds to a small hill. If they all sprout, thin down to about 3 plants per hill.

With seedlings, you have to prepare your garden area by digging the soil thoroughly so that it’s loose. To protect the roots, you should loosen the soil at least 6 inches deep. If you are using larger seedlings, you may want to dig deeper. Mix in compost or aged manure, for these heavy-feeding plants.

As mentioned, zucchinis have long tap roots, so you need to be careful when you transplant that you don’t break the roots. Dig a hole deep enough that you can set in the seedling without having to fold up the longer roots.

If you are planting more than one hill of zucchini, you should allow plenty of space between them. Bush plants need at least 3 feet on all sides because they will get quite large. Vining zucchini that are being grown upward on a trellis can be about a foot and a half apart.

Growing Instructions

Water your zucchini frequently and don’t let them completely dry out, especially once they start to set fruit. Give them a good soaking about once a week. Take care while watering to keep the water off the leaves as much as you can to reduce any problems with fungus or mildew.

Once the plants have grown to a decent size, their broad leaves will help keep the area weed-free by shading out invading plants. To keep your vines thriving, give them a good doze of fertilizer each month of the summer.

You can control the amount of fruit you get from each vine by picking the extra blossoms off once a few zucchini have begun to form. If left to themselves, a zucchini vine will keep on producing all through the summer until the weather gets too cold. The blossoms don’t have to go to waste either. Add them to a summer salad for some color. They’re edible and tasty.

Containers

Zucchini generally isn’t considered a container-friendly vegetable, but there are a few varieties that grow in a fairly compact bush that would work in a large container. Little Gem or Eight-Ball form bushes with fruit in the middle instead of long vines, and work fine. Your container should be 2 to 3 feet across, and at least 3 feet deep.

Pests and Diseases

There are several pests you need to watch for when growing zucchini. When it comes to insects, Striped Cucumber Beetles and Squash Vine Borers are your worst enemies. The beetles are fairly obvious on the leaves and blossoms and can be picked off by hand. Organic insecticides with pyrethrin can work quite well. If you are really struggling with beetles, you may want to even cover your young plants with a light sheet of mesh netting until the blossoms form. You need to remove it though, or your plants won’t get pollinated.

The vine borers are hard to deal with because they dig into the stalk, making them very hard to detect until your plant is already dying. You can cut into the stalk (along the length, not across) and pick out the insects, which may or may not kill the plant anyway. If you bury the cut portion, it may heal and even grow new roots.

For diseases, you need to watch for wilt and powdery mildew. Bacterial wilt can be spread by cucumber beetles, which is another reason to control those insect pests. If your plants develop wilt, there is little you can do. The leaves will turn yellow, and wilt right to the ground. It can happen practically overnight. Pull up the plants before others get infected.

The other threat is powdery mildew, which looks like powdery dust on the leaves of the plants. It thrives in humidity, so do your best not to wet the leaves during watering. Also, water the plants early in the morning so any water on the leaves can dry before nightfall. You can spray the plants with a fungicide as soon as you see the powdery spots. The effected leaves will eventually yellow and drop off.

Harvest and Storage

And while it might be tempting to let your zucchini grow really large, the best flavor comes with the smaller fruit. Large ones start to get woody, and the seeds are getting hard inside as well. Pick them around 6 to 10 inches long. They will grow quite quickly, so plan on checking the vines every couple of days.

It’s almost inevitable that one or two zucchinis will be missed, and you will discover a huge one growing in a corner somewhere. You can still use it, but it will likely work best grated in a baked recipe (like muffins).

Handle the fruit carefully once you’ve picked them off the vine. The skin is very thin and it can get scratched or bruised easily. Zucchinis don’t hold their flavor very long after picking. You can store them in the fridge but should use them up within a week.

6 Responses to “How to Grow Zucchini”

Craig Says:
March 16th, 2012 at 5:12 pm
How often should you water and for how long. I like to grow squash(summer and butternut)zucchinis, beats, carrots, tomattos,beans, and pumpkins but can never tell if I’m over watering or underwatering. My dad use to do the watering for me when I was younger and I believe he watered every day for probably 5 to 10 minutes but I’m not positive as we got older we got built in sprinklers and they got watered every morning for 15 minutes but if I’m using a hose that seems to be way too much water to me. Any advise?
Dave Says:
July 5th, 2012 at 7:08 pm
Thanks for the useful info about growing. One slight mod is suggested: zucchini squash is a poor source of Vitamin A, and only a modest source of Vit. C and fiber. The manganese content isn’t included in USDA nutrient data, so I don’t know how you have decided it is a good source of this trace mineral. I would doubt it, though, because the various squash species are generally not good sources of most trace minerals. However, like most plant foods, squash is a good source of potassium.

Nutrient values can be easily looked up here: http://ndb.nal.usda.gov/ndb/foods/show/3247
bill Says:
July 8th, 2012 at 2:52 pm
my zucchini plant roots on not deep and no luck in containers
Shelly Says:
July 9th, 2012 at 7:18 am
I found a bag of old opened potting soil in my shed. It was dry and didn’t look fresh. Does potting soil go bad or could out door animals cause any kind of fungi or bacteria that will kill plants if I used it?
Lin pierce Says:
July 29th, 2012 at 10:41 am
We’re growing a second crop of zukes and yellow squash as we lost many to squash borers. I know it is recommended to pile dirt over the stems after squash borer “surgery” has been done as the plants can then grow some new roots. This made me wonder if planting new seedlings deeper than what is usually recommended would help to make the new plants stronger, say up to the first set of leaves like we do with tomato plants? Is this worth trying?

Also, No fear of squash borers now as their cylce has the caterpillars coming out in late June, right?

Thanks for your attention.
Lin
Shaun McMahon Says:
April 3rd, 2013 at 10:21 am
To grow in containers how important is the size of the container? – can you grow Raven zucchini in a 1′ by 1′ container