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Some people are born with a green thumb and love the idea of having a garden full of all kinds of produce. Others of us struggle to keep basic houseplants alive and feel overwhelmed by the idea of trying to grow our own food. Anyone who's tried to grow a garden knows it's not as simple as just throwing some seeds in the dirt and waiting, and if you don't really enjoy it, gardening can feel like it isn't really worth the time or effort.

However, there are some fruits and vegetables that are worth trying to grow, even with some initial cost and time investment, simply because growing them is so much cheaper than buying them. That's not automatically true of all produce, but for these six foods, if you succeed in nurturing them to harvest, you can save a bundle vs. buying them at the supermarket. (Yes, even when they're on sale.)

Growing your own food can save money, especially with certain crops.Photo credit: Canva

Tomatoes

There's nothing like a fresh tomato right off the vine, first of all, so that's a reason to grow your own tomatoes all by itself. But tomatoes are fairly easy to tend and cost approximately six times less to grow than to buy by some estimates. And that's even if you include some initial cost for soil, a pot, and a starter plant. If you already had a garden plot and grew from seed, it would cost you even less.

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Tomatoes can be frozen or canned to make a large harvest last longer than the growing season and then used in sauces and soups. Baby or cherry tomatoes can be frozen whole and roasted in the oven straight from the freezer.

Zucchini and other summer squash

Have you ever had a friend with a zucchini plant who tried to give you zucchini every time you turn around in the summer? Once these famously prolific plants start poppin', they don't stop.

You can grow zucchini in a bed or in a pot. You can also grow it vertically, like this:

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Zucchini's cousin, yellow squash, is similar. Before you know it, you've got squash coming out your ears. You can give it away, but you don't have to. You can slice it up and freeze it for soups or stir fries after the harvest comes to a close.

Peppers

If you buy bell peppers, you know they can be on the spendy side, especially if you buy organic ones. Growing your own can save a pretty penny, though, especially once you get a garden plot or container established for them.

One gardener demonstrated how a successful crop of pepper plants in his raised bed can save approximately $320 a year, and that's including initial startup costs. Savings would be even greater in subsequent years since most of those costs aren't recurring.

Peppers can be frozen fresh to be used in cooked dishes later. (Are we getting the hint that a large freezer is a necessity when you have a garden?) And the grow-your-own savings goes for all kinds of peppers, not just sweet bells. Poblanos, jalapenos, serranos, chili peppers—you can have a whole array of pepper plants right at your fingertips.

Lettuce

Salad lovers, rejoice, because growing your own leafy greens can be a big boon for your diet and your pocketbook. Romaine lettuce in particular is a fast-growing green that replenishes in just a week or two, so if you have a few of these babies planted you'll be eating fresh salads on the regular through the spring and summer (and into fall as long as the weather holds).

Lettuce is a comparatively easy crop to grow, so don't be intimidated if you've never done it.

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To harvest lettuce, you can cut off the largest, most mature leaves to eat, leaving the interior of the plant alone so it will keep on growing. Another method is to slice the whole lettuce plant straight across, as long as you leave the "crown" in the center so it can keep regrowing.

With lettuce, unfortunately, you don't get the ability to freeze for later, but having fresh salads for many months of the year makes up for it.

Cucumbers

If you enjoy the fresh, crisp crunch of a cucumber, growing your own is where it's at. While how much you can save will vary depending on where you live, where you shop, and how successful. your crop is, a cucumber patch can yield a ton of cucumbers, especially if you learn some tricks specific to cucumber growing.

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One of those "tricks" is to regularly harvest your cucumbers. The more you pick, the more the plant will produce—nifty, eh?

Another tip is to keep them watered well. Cucumbers are largely water, so they do require a lot of water to grow. Just don't get the leaves wet—keep the watering at the base of the plant.

Fresh Herbs

This might be the most cost savings you'll see in a garden, especially if you use a lot of fresh herbs (which you should—they're so good!). Have you ever bought fresh herbs in those little plastic clamshells at the store? They're usually $2 to $3 each for just a handful of leaves or sprigs, and they don't stay fresh for long. An herb garden can save you tons and provide a nonstop source of fresh flavorings.

Basil, oregano, rosemary, and mint are particularly easy to grow and you can even grow them in your kitchen.

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But a full-fledged herb garden is even more fun. Cilantro, parsley, holy basil, chives, dill, thyme—there are so many herbs you can grow yourself. In fact, you may find yourself using more herbs if you grow them since you won't have to spend money on them at the store and they need to be harvested in order to keep growing. Aromatic, healthy, delicious, and cheap—win, win, win, win.

And you can dry or freeze excess herbs to use for cooking later as well. So much winning.

Growing your own food isn't always easy, but learning how to garden crops that can save you big money is definitely worth the time and energy investment to try.