Tomatoes are a great starting point for hydroponic gardeners. They’re relatively easy to grow, they’re tasty, they’re nutritious. There are a wide range of tomatoes you can grow, so you’ll never be bored. They can be grown year round and can easily become a core staple of your diet.
Let’s take a look at some of the essential elements of growing hydroponic tomatoes.
Choosing Seeds and Varieties
There are a lot of varieties of tomatoes you can grow with a hydroponic setup. Brandywine is one of the most popular and common. Other vining tomato varieties include Giant Beefsteak and Burpee Big Boy. Matusalah is a fantastic variety to go for, though seeds are harder to find.
As for bush types, both Celebrity and Tiny Tim are quite popular. Then of course you have Cherry Tomatoes (aka “Baby Tomatoes”) that are always a favorite for salads.
It’s very important that you grow your tomatoes from seeds. With traditional planting, it’s common to just use part of an existing plant to grow a new plant. This is not a good approach for hydroponics. Bringing in parts from existing plants will introduce diseases, dirt and garden pests to your hydroponic setup.
Getting the pH Right
Tomatoes thrive at between 5.8 pH and 6.3 pH. However, tomato seeds tend to grow better in about 4.5pH. Start your rock wool at 4.5pH, then move it up to 5.8-6.3 pH. Then make sure you test your pH levels regularly and adjust your pH levels accordingly.
Getting the Lighting Right
Tomatoes are best grown with metal halide lights. The lights should be placed directly above the plants, so the light shines on the leaves but not the roots. The metal halide lights can damage the roots if they’re exposed to the lights.
Don’t turn the lights on until the seeds sprout. Once sprouted, shine the lights on the sprouts for about 12 hours a day. Once the sprouts grow into plants, the light should be left on for 18 hours a day instead. During the remaining time, the plants should be left in total darkness. That means no ambient light.
If you are on a tight budget, you can try to build a one yourself. I managed to build a grow light for about $10 in about 30 minutes.
Regulate Temperature and Air Flow
The tomatoes should be kept at 18 to 24 C (65 to 75F) during the day (e.g. when the lights are on.) When the lights are off, the tomatoes should be kept at 12 to 18 C (55 to 65 F.)
Adding or removing fans can help you regulate the temperature. Between 1 to 4 oscillating fans will do the job, depending on how large your hydroponics setup is. Make sure the fans aren’t pointing directly at the tomatoes, as that can dry them up.
Growing tomatoes is fairly easy and incredibly rewarding. Once you’ve set everything up, the garden will require very little management. In just a few short weeks, you’ll have several handfuls of delicious, ripe tomatoes ready to eat!