Growing Zucchini in a Raised Bed: Tips for a Bumper Harvest

While many gardeners plant zucchini in traditional rows, growing in raised beds has several perks. Raised beds can be placed just about anywhere you want, making it easier to watch rapidly growing zucchinis. But on top of that, growing zucchinis in raised beds gives you more control over soil quality, reduces weed and drainage issues, and helps the soil warm up faster in spring so you can plant even earlier.

So, are you ready to try your hand at growing zucchini in raised beds? If you are, this guide will walk you through the basics and provide space-saving tips, trellising options, and simple tricks for taming sprawling zucchini vines into submission!

Preparing the Raised Beds

Gardeners’ main concern about keeping zucchini in raised beds is whether or not their plants will have enough space to thrive. But if you do a bit of prep work before planting, you can ensure your raised garden is set up just right for zucchini, and any other plants you want to grow!

As far as sizing goes, raised beds can be as long as you want them, but they should be a maximum of 4 feet wide to make weeding easier, and at least 12 inches deep to accommodate zucchini plant roots. When it comes to soil selection, think rich and well-draining, and make sure the soil has a slightly acidic to neutral pH of around 5.8 to 7.0. Store-bought raised bed soil mixes work well, but you can also make your own DIY soil by blending together equal parts sand, compost, and topsoil.

Once you’ve selected your soil and a raised bed frame, find a suitable location for your garden that receives at least 8 hours of direct light per day, and that’s near a water source and protected from strong winds. This will save you from having to lug water back and forth to water-loving zucchinis and make sure pollinators don’t get blown away from zucchini flowers. If the location is in an area where you can keep an eye on growing zucchini, even better!

To install new raised beds, first remove rocks, weeds, and grass from the area, and lay down newspaper or cardboard over the soil to keep weeds from resprouting. Install your raised bed frame, fill it with soil, and then blend in some compost, aged manure, worm castings, fish emulsion, alfalfa or kelp meal, or a slow-release fertilizer to enrich the soil with nutrients and fuel the growth of hungry zucchinis.

Picking the Right Zucchini Variety

Zucchini plants come in vining or bush-type varieties, and both types of plants can be grown in raised beds. However, their growing and spacing needs vary slightly.

Compact, bush-type zucchinis, like ‘Eight Ball’ and ‘Bush Baby,’ stay relatively compact and can be grown in rows in raised beds without any trellising. These small plants generally need to be spaced about 1 ½ to 2 feet apart; however, you may be able to squeeze a few extra plants into your garden by slightly staggering your rows.

Vining or trailing zucchinis, like ‘Shooting Star’ or ‘Black Forest,’ are bigger plants that need trellises, mesh netting, or cages to keep their vines more manageable. These plants also typically need a little more room in raised beds and should be spaced about 2 to 3 feet from their neighbors. If possible, install vertical structures such as trellises as well as stakes before planting vining zucchinis to prevent accidental stem breaks, and consider making a DIY trellis with a cattle panel and T-posts to save money and grow lots of vining zucchini together!

How to Plant Zucchini

Zucchini can either be grown from transplants or seeds directly planted in the garden in spring. However, direct sowing is usually recommended as zucchinis have fragile root systems and don’t transplant well. 

To direct sow zucchini seeds, wait until about 2 weeks after your last frost date—when soil temperatures are around 65 to 70°F—and then plant zucchini seeds about 1-inch deep in your raised beds. Sow vining zucchini just a few inches away from their trellises, and follow the spacing recommendations for the type of zucchini you’d like to grow. That means at least 1 ½ feet spacing for bush-type plants, and 2 feet spacing for vines! If you want to be doubly sure your seeds sprout, overseed your plants by sowing 2 to 3 seeds per planting hole and then thin out the weakest seedlings when your zucchinis sprout true leaves.

If you’re growing other plants in your garden or want to grow zucchini with companion plants that attract pollinators, like flowering dill, nasturtiums, calendula, borage, and sweet alyssum, you’ll need to follow proper spacing guidelines with these crops too. Zucchini of any sort should be grown at least 2 to 3 feet from other plants to improve air flow in your garden and keep diseases, like powdery mildew, from creeping in!

More tips to try:

• Want to plant earlier? Warm up your soil in advance by installing black plastic over raised bed soil a week or two before planting.
• Late season frost on the forecast? Protect tender zucchini seedlings with cloches, frost blankets, cold frames, or row covers.
• Struggling with squash vine borers? Plant zucchini seeds in midsummer, rather than spring, to avoid the worst vine borer problems.

Caring For Your Zucchini

After planting zucchini seeds, water your seedlings well and keep on watering them regularly whenever the top 1-inch of soil feels dry. Remember, plants grown in raised beds need more water than plants in-ground gardens, and irregular watering can lead to issues like blossom end rot. In cool weather, zucchinis may only need to be watered a few days a week, but they may need daily watering as temperatures rise!

To cut down on watering, add mulch around the base of zucchini plants when they’re a few inches tall and consider installing drip irrigation lines or soaker hoses too. Watering zucchinis at the soil line can limit the amount of water that’s lost to evaporation, but it’s also the best way to avoid fungal diseases, like powdery mildew.

Aside from watering, zucchini plants should also be fertilized regularly throughout the growing season, either with a liquid or granular fertilizer. Slow-release, balanced fertilizers or liquid fertilizers intended for tomatoes are usually the best choice for zucchini, and these should be applied once zucchini plants begin to flower and reapplied every 10 to 14 days after that. However, it’s important to follow the instructions on fertilizer packaging as application rates and timelines can vary widely depending on the product you’re using.

Regularly watering and fertilizing zucchinis should help your plants grow big and produce well. But you can also improve the growth of zucchinis by monitoring your plants for pests and growing them near pest-repelling companion plants like dill and cilantro, which can deter squash vine borers and squash bugs. You may also need to “teach” trailing-type zucchinis to climb their trellises with a bit of garden twine!

Harvesting Your Zucchini

Zucchini plants typically produce male flowers before female flowers emerge, so don’t be alarmed if your plants drop their first flowers without fruiting. If pollinators are active in your garden, they should do all the pollination work for you when the female zucchini flowers bloom. Reducing pesticide use and companion planting should attract more pollinators to your garden, too; however, you may need to hand-pollinate zucchini flowers if you don’t see any pollinators around.

Most zucchinis start fruiting about 60 days after planting, and it pays to be well-prepared when they do! These plants are massive producers and should be harvested regularly to keep plants productive and to ensure their stems don’t break under the weight of hefty zucchini fruit.

For best flavor and texture, harvest zucchinis when they’re tender, slightly immature, and about 4 to 8 inches long by cutting the zucchini off the plant with a sharp knife. Cutting, rather than pulling, zucchinis off the vine limits damage to zucchini plants. But zucchinis also last longer if you leave about 1-inch of stem attached to each fruit!

With proper care, zucchini plants can continue to fruit for months. However, any remaining zucchinis should be harvested before cold weather strikes, as they won’t survive frost.

Summary

Even compact zucchini plants can be incredibly productive in small raised beds and fill your kitchen with all the zucchini you want. Fresh zucchini lasts about a week in the fridge, but you can always freeze or pickle your extras, or share them with neighbors and friends. Just be warned: you may need a backup plan to get rid of your extra zucchinis once your neighbors find out how prolific zucchinis can be in raised beds and start growing their own!