About cucumbers
Honeybee on Helenium - we’ve grown this perennial for over 15 years, and it’s ALWAYS loaded with pollinators. Great low maintenance flower to attract pollinators!
Cucumbers are part of the Cucurbitaceae family, a widely popular group also known for bringing us watermelons, pumpkins, and squash. The fruit itself is classified as a pepo, which is a type of berry. In botany, a berry is a fleshy fruit without a pit produced from a single flower containing one ovary. So, the category is actually very wide, and in addition to cucumbers, you could eggplants and bananas are also berries. Which is worth noting only because it may come in handy the next time you play Trivial Pursuit.
Cucumber berries are typically pollinated by bees, in particular honeybees and bumblebees. Most cucumbers can’t self pollinate, which means that they need the pollen of another plant to form seeds and fruit. So as a general rule, you never want to plant just one cucumber, unless it’s parthenocarpic.
This is a big botanical word that means they create fruit without pollination, and those fruits don’t have seeds. In seed catalogs they are often called either “burpless” or “seedless.” So if you do only want to plant a single cucumber, or only have space for one, make sure you pick out one of these varieties.
How to trellis cucumbers
Cucumbers grow best when they have support. We prefer to grow our cucumbers vertically using the Freyr trellis set up to 5’ in height. Vertically trained cucumbers are easier to harvest and are less susceptible to pests and diseases.
Vertically growing cucumbers also allows you to maximize your growing space by keeping them from sprawling all over your garden. Cucumbers have tendrils so they’re very easy to grow vertically. Their tendrils will grab onto the vertical support, but it can also be helpful (but not always necessary) to twist your plants around the twine every now and then, and use compostable trellis clips when your plants are heavy with fruit.
When planting cucumbers on a vertical string, space your plants 12” apart. After planting, throw a piece of twine over the top of your support so that you end up with both ends of the string at soil level with your plant. Then tie a loose knot around the base of your seedling, or use a compostable trellis clip to secure the string to the plant.
If you’re more of a visual person, here’s a short video on how to do this :)
Types of cucumbers
When you get to the seed catalogs, the main categories of cultivated cucumbers you’ll find are slicing, pickling, and seedless (aka parthenocarpic).
Slicers are grown to eat fresh and are generally longer, smoother, and have tougher skin. Although any cucumber can be pickled, commercial pickles are made from cucumbers specially bred for uniformity of length-to-diameter ratio.
Picklers usually grow to about (3 to 4 in) long and (1 in) wide so they fit easily into jars. Compared to slicers, picklers tend to be shorter, thicker, and have a bumpier skin.
Seedless varieties are supposed to be sweeter and have a thinner skin than other types. Thinner skins and lack of seeds is supposed to reduce the fruit’s bitterness, which is where the name “burpless” came from, since they are supposed to be easier to digest.
Mid-summer Straight Eight cucumber harvest
More cucumber basics
What you eat: The fruit.
Recommended varieties: Marketmore, Straight Eight, Suyo Long, Tasty Treat Slicer, Armenian.
Hardiness: Cucumbers can’t tolerate frost, and grow best at 60°F and up.
Seed information: Germination temp. 65°– 100°F, optimal 86°; germination time 6 days at 68°, 3 days at 86°. Seed viability 2–5 years.
Mature plant size: Up to 5–6 ft. tall in a trellis, or 5–6 ft. long if spread on the ground.
How to plant: In cooler climates, cucumbers are best grown from transplants, but in areas with longer, warmer seasons, cucumbers can easily be grown from seed ourdoors. Cucumbers can be direct-seeded once the soil has warmed above 60°. Space plants 1-2 feet apart.
When to plant: Cucumbers like it warm, so it’s best to wait until the weather has really warmed up to set out transplants. If the weather is still cool and rainy, don’t be afraid to wait.
How much to plant: Expect to harvest 2–5 lb. of cucumbers per plant. 1 or 2 plants is plenty for most gardeners, but if you plan to make a lot of pickles, add another 3 or 4 plants.
When to fertilize: Before planting, and at 3 and 6 weeks after transplanting. Use 1⁄4 cup balanced fertilizer per plant, or liquid fertilizer.
A Dandelion Yellow Freyr trellis planted ½ in poles peas, and then other ½ with cucumbers.
Succession planting: Cucumbers grow to maturity in around 60 days. This means in many growing regions there’s enough time to plant multiple successions of cucumbers as a way of extending your harvest window.
For example, you may plant your first crop in May for a summer harvest, and then a second planting in August to extend your harvest into the early fall. Cucumbers’ relatively short lifespan also makes them a great crop to succession mid-summer after a different spring crop. An example of this would be planting cucumbers where your snap peas were growing, once they’re done producing.
We’ve found that this technique works really well when growing on the Freyr trellis, or on a similar vertical growing structure, and allows you to really maximize your vertical growing structure by growing more than one crop on your trellis per season.
General care: Watch for slug, snail, and cut-worm damage on young seedlings. Cucumbers like plenty of water when setting fruit, so make sure they have an ample supply. Underwatering may lead to very thick skin on your fruit.
Pests: Cucumber beetles, leaf miners, and squash bugs may try to eat the foliage.
Diseases: Powdery mildew, downy mildew, Verticillium wilt, and black rot.
Container suitability: Good. Use 3 gal. pots or larger, or anything at least 9 in. deep.
When and how to harvest: Harvest cucumbers when they’re about the size—depending on the type—that you’d expect to see in the grocery store. After the first harvest, check the plants every 2–3 days to make sure the cukes don’t get too large. Frequent harvesting encourages the plant to produce more fruit and keeps the skins from getting tough. Cucumber stems can be pretty tough, so scissors or a knife can make it much easier to remove the fruit from the plant.
Cucumbers are mostly water (90–95 percent but still give you a healthy dose of potassium and antioxidants. They are almost always picked “green,” which refers to their color but also the fact that they are immature fruit. If left on the vine, a cucumber will eventually ripen to yellow. At that point it is mature but also very bitter and not so good for eating (although there are types that are intended to be eaten yellow, such as the “lemon cucumber”).
Harvesting pickling cucumbers growing vertically on the Freyr trellis.
Storage and preservation:
Fridge: Cucumbers keep best at 40°–50°F, but will do better in the refrigerator than if left out at room temperature. Expect them to keep a few weeks.
Canned: Pickles. We recommend refrigerator pickles for a quick and easy solution.
Nerding out on cucumbers
Cucumber’s scientific name is Cucumis sativus. Many readers may recognize the species name sativus, or the variation sativa, from certain “herbs” they keep around the house. In fact, this species name is exceedingly common. To name a few other sativas you may already be growing: Allium sativum (garlic), Daucus carota subsp. Sativus (carrot), Eruca sativa (arugula), Lactuca sativa, (lettuce), Pastinaca sativa (parsnip), and Pisum sativum, (peas).
Sativa, sativus, and sativum are Latin botanical adjectives that mean “cultivated”. Cultivation is the act of caring for or raising plants (i.e. gardening). So basically, these latin names are just telling us that all of these plants are cultivated varieties descended from wild cousins.
In fact, it’s believed that cucumbers have been cultivated for at least 3,000 years. The cucumber originated in India, where a great many wild and cultivated varieties still exist. Which may prompt you to wonder, “How do people even figure out where plants originate?” Well, when trying to identify the origin of a species, botanists look for what is called a center of origin (or center of diversity). The basic idea is that, if you find an area with a lot of cucumbers and those cucumbers contain a huge range of genetic variability, this is probably the area where they originally evolved.
In addition to earning world class sleuth credibility, locating the origin of a crop like cucumber is essential to effective plant breeding. Knowing where a plant comes from allows you to locate wild relatives, related species, and find new genetic diversity. This is especially important today as we face climate change and the untold changes to crop pests and diseases it may cause.
We could literally talk about cucumbers all day, but probably shouldn’t. If you haven’t planted any in the garden yet, or if you planted them early and they didn’t survive, now is a great time to get them in the ground. You’ll be joining in the odyssey of over 3,000 years of human history with this plant. Reason enough to plant at least two (or one parthenocarpic) specimens in the garden this season.
Colin McCrate has been growing food organically for over 20 years. He worked on a variety of small farms in the Midwest before moving to the west coast in 2003 to teach garden-based environmental education. He founded the Seattle Urban Farm Company in 2007 with the goal of applying years of horticultural and agricultural expertise to help aspiring growers get projects off the ground or more accurately; in the ground.
He has helped guide hundreds of urban farmers through the design, construction and management of their own edible landscape. Colin is the author of three books; Food Grown Right, In Your Backyard (Mountaineers Books, 2012) and Grow More Food (Storey Publishing, 2022); and is a garden writer for the Seattle Times.