Should You Grow Cucumbers Directly from Seed in the Garden?

Planting Cucumbers 101

Hey there, have you grown your own cucumbers yet? You should! Cucumbers from the garden are so much better than the cucumbers from the grocery store. I can't wait to have bushels of cucumbers coming out of my garden this summer.

There are three ways you can get started growing cucumbers. You can transplant cucumber seedlings that you start indoors, you can plant cucumber starts purchased from your local nursery, or you can direct sow some cucumber seeds right into the garden. But which is your best option?

The Best Option Is to Direct Sow Your Cucumbers

Direct seeding cucumbers in the garden as soon as the weather is warm enough is the fastest, easiest, and least expensive option. It's also the route with the highest chances of success (assuming you don't plant those seeds way too early).

If you're growing any kind of cucurbit—whether that's cucumbers, squash, or watermelons—I typically don't recommend moving the plants. They're fragile little seedlings that get stressed out very easily. It's best to start with seeds in the garden if you're at all able.

What I've found over the years is that cucurbits that were direct sown in the garden will catch up to those plants that were started indoors and then transplanted as seedlings. Within a matter of weeks, they'll even outgrow those transplants. One great thing about plants in this family is they do get big pretty fast once they're up and growing.

When to Grow Cucumbers

Cucurbits are, for the most part, warm-season plants. A couple like it hot (like suyo long cucumbers), but none of them like it cold. I can't think of a single plant in this entire family that can tolerate frost.

So when I say plant cucumbers in the spring once all threat of frost has passed, I mean it. Cucumbers have zero frost tolerance. They thrive when the temps are between 65°F and 84°F. If you live in a colder climate, they're the quintessential summer crop, and if you live somewhere warmer, they'll probably grow best in your spring and fall growing seasons. Once you move into a hot season, when temps are regularly above 90°F or so, most cucumber varieties will drop their flowers before they can form fruit.

How to Plant Cucumber Seeds in Your Garden

Again, direct sowing cucumbers is the best and easiest way to grow cucumbers.

Start with a raised bed filled with well-draining soil (I recommend a sandy loam soil blend with plenty of coarse sand and compost). Make sure to plant your cucumbers next to a sturdy trellis they can climb. I love growing cucumbers on obelisk trellises.

If you're container gardening, look for a cucumber variety that's container friendly and choose a container that's at least 18 inches across so you can fit a small obelisk trellis inside for support.

Use a dibber or hori hori to make planting holes that are about half an inch deep and spaced about 4 to 6 inches apart. If you're growing cucumbers around an obelisk trellis, it's great to plant one seed beside each leg.

The back of the seed package might tell you to plant two to three cucumber seeds per planting hole. I've found that if you get your seeds from reliable seed companies like Baker Creek, then almost all your seeds will germinate. So I rarely put more than one seed in a planting hole.

Barely cover the seeds with soil, and then water the seeds in. Keep the soil watered each day until you see your little cucumber sprouts emerge.

How Deep Should You Plant Cucumber Seeds?

Cucumber seeds should only be planted about 1/2 inch deep. The general rule is to plant a seed no more than twice the depth of the seed's width. Half an inch is barely anything at all. Too many beginner gardeners plant seeds super deep, and when those seeds never come up, they think it's the seed's fault. In reality, those poor little plants spent all their energy just trying to make it to the soil surface and then gave up before they ever had a chance to feel the sunlight on their leaves.

How to Transplant Cucumber Plant Starts from the Nursery

Let's say you're walking past all those adorable little baby plants at the nursery and you just can't resist. I feel ya. I've bought cucumber starts from my favorite local growers before. I do recommend going to your local nursery, though, instead of buying your starts from a big box store. They're more likely to have been grown locally and organically.

You'll want to plant your cucumber starts as soon as you bring them home if the weather is cooperating. That way, those plants won't have to linger in their tiny little pots too long. Basically, if the plants are 2 to 3 inches tall and it's warm enough outdoors (once again: no threat of frost), plant them outside.

You might notice there are two or more plants growing in the same little container. This is no bueno in terms of long-term growth because the plants are fighting over available resources. When that happens, you have two options. You can try to gingerly pull their roots apart, or you can take a pair of pruners and cut off the less-healthy-looking plant at the soil level. With the latter option, you'd only plant the healthier plant. It's always a hard call to make. I like to try my luck and pull the plants apart, even though that does result in some root damage to both plants.

Add some finished compost to the planting area. This will give your new plants some extra food.

Plant your cucumber seedlings right up next to a sturdy garden trellis. I love to plant cucumbers around the outside of an obelisk trellis, and the goal is for each vine to climb a vertical pole.

Each planting hole should be just as deep as the root ball of your seedling and twice as wide. Carefully place your seedlings inside the holes, avoiding disturbing the roots. Give the planting area a nice, deep watering. Pinch off any tired-looking leaves that might drain energy from the plant. We want all the energy to go to the roots and healthy leaves.

These plants will likely struggle over the next few days, especially if it's warm. Keep them well watered.

How to Start Cucumber Seeds Indoors

Even though cucumber seedlings don't like to be transplanted, some people just like to feel ahead of the game. If you get a thrill from knowing that your warm season plants are growing inside and getting ready for your spring gardening season, you do you, okay?

I recommend starting your cucurbit seeds in 4-inch pots (the type that you get from nurseries when you buy plant starts), instead of smaller cells. That way, you won't have to transplant your cucumbers at all before it's time to move them to the garden space. They can go straight from these pots to your raised beds in about a month.

Fill those pots with compost and then plant one to two seeds per pot. Set them in a non-draining tray so that you can water them from the bottom (those flimsy little pots should have drainage holes at the bottom that will allow the soil to take up water). Turn on grow lights as soon as the cucumbers sprout.

You should see little sprouts in about 5 to 10 days. 

Time to Plant Some Cucumbers!

I hope this inspires you to plant some cucumbers as soon as the weather is warm, preferably by seed, but no judgment either way! With some proper care, you'll soon be enjoying the simple pleasure of eating a cucumber fresh from the garden no matter which planting route you took.

Thanks for bringing back the kitchen garden with me! Stay cool like a cucumber, y'all.