Over the last couple of years, I’ve slowly made my way through most of the vegetable family.
But one vegetable I never tried?
Cucumbers!
I guess they didn’t seem all that exciting to me..
But I recently got a new machine, the Letpot LPH-Max, and suddenly found myself with extra garden space.
The Max’s large 7.5 liter water reservoir and trellis system seemed perfect for cucumbers – so I decided to give them a shot!
Here’s a quick guide to growing cucumbers indoors.
How to Grow Cucumbers Indoors
Cucumbers are a little more difficult than growing herbs or lettuces… but easier than growing peppers.
Here are my best tips for growing hydroponic cucumbers.
Quickly jump to a section:
Hydroponic Cucumbers
I grow all of my vegetables indoors, hydroponically, because it’s a cleaner, faster and easier method of gardening.
I primarily use all-in-one indoor garden machines that take care of the watering, lighting and growing.
It makes it much easier to grow vegetables indoors when the bulk of the work is taken care of!
For cucumbers, I’d recommend a medium sized machine.
Read more: The Beginner’s Guide to Hydroponics
Cucumber plants can get quite large, and a machine that can support vertical growth, through poles or trellises (or a DIY trellis) would work best.
In particular, I’d recommend:
Read more: My Complete Indoor Garden Setup, with Links!
Seed Starting
There are tons of different varieties of cucumbers, ranging from mini cakes to pickling cakes to long slender extra large types.
The best part about growing your own vegetables is you can choose varieties you’ll never find at the grocery store or farmer’s market.
I always buy non-GMO heirloom seeds from online seed companies.
Some of my favorite heirloom seed companies for cucumber seeds are:
They all have a great selection of organic and non-organic seeds to choose from.
It’s important to buy your seeds from reputable seed companies, as the seeds will be high quality, true to type and have higher germination rates.
The two varieties I grew are these pickling cukes and these mini slicing cukes.
Germination
Cucumber seeds germinate incredibly fast – you should see them sprout in under 4 days.
From there, the plants grow quickly, so cucumbers are an excellent vegetable to grow if you’re impatient.
I’ve found that cucumber seeds can be sown in a hydroponic sponge directly in the indoor garden.
Because they sprout so quickly (and as long as you’re using good quality seeds), planting 1 seed per sponge is fine.
Read more: The Best Affordable Indoor Garden Supplies
cucumber plants will shoot out in practically every direction
Growth
Cucumbers are quick to grow, and most varieties bear fruit in 30-45 days.
The vines can try to climb and grow in every direction, so I really recommend a trellis.
The Letpot Max has a trellis system that you can purchase separately, which is fantastic for climbing plants like cucumbers.
It’s a tiered trellis system, so you can add layers as your plants grow.
This helps keep the cucumbers off the base of the machine and keeps growth manageable in an upward direction.
It also allows you to better see the flowers and fruits forming, so that you can get higher pollination rates.
And, a vertical trellis will improve airflow which is crucial for indoor plants.
using a fan helps increase pollination rates for your indoor vegetables
Pollination
Most cucumbers will need some help with pollination.
Depending on which variety you have, you may need to pollinate the male and female flowers together.
You’ll know a cucumber has been successfully pollinated when the mini fruit starts to swell and the flower dries up.
If the fruit turns yellow or starts to look dry, pollination wasn’t successful.
these 3 baby cucumber fruits weren’t successfully pollinated – the fruit is gradually withering, drying up and turning yellow
It may take a couple tries until you get your first cucumber fruit!
I also recommend getting a room fan like this.
I use one to help pollinate all of my indoor veggies, since I don’t have the time (or want) to manually pollinate all my gardens.
a quick video demonstrating how I manually pollinate my cucumber plants
Harvesting
Cucumbers will grow rapidly once they’ve been pollinated.
If you notice the fruit no longer seems to be getting larger, it’s likely reached its full size.
Harvesting early is generally better than harvesting too late – young cucumbers will have less seeds, stay crunchy and sweeter.
Look for a shiny exterior skin – that’s when the fruit is at peak harvest mode.
harvesting cukes! I grew both a squat pickling variety and a slender mini slicing variety
Lettuce Grow Discount Code
Use SHER125 for $125 off any farmstand
Growing Cucumbers Indoors
And that’s it!
My quick and easy guide to growing cucumbers indoors in a hydroponic garden.
Overall, I’d say cucumbers are straightforward to grow – about a 5/10 on the difficulty scale.
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