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Hydroponics: which vegetables can you grow hydroponically? Hydroponics is a technique for growing plants without soil. You can grow any vegetable hydroponically, but some vegetables are better suited to the process than others.
This new technology of farming in nutrient solutions without soil is similar to aquaculture (fish farming) in that plants do not have an area in which they can establish a symbiotic relationship with the necessary microorganisms.
The hydroponics technique consists of adding macronutrients and micronutrients directly to the water circulating through the plant roots. The plants are fed with mineral solutions and take what they need through their roots.
They use macronutrients such as potassium, calcium, magnesium, and phosphorus; and micronutrients like iron or zinc.
We have listed some vegetables you might want to try in your hydroponic garden below!
Cucumbers like warm weather and a lot of sunlight. They need at least 8 hours of sunlight to grow big and juicy. It is best if the soil pH level is between 5.5 and 6.5 for optimal results. This vegetable usually does pretty well in hydroponic systems, given that it needs plenty of space for its vines to spread. After you plant the seeds, allow them to germinate and then hold off on fifteen hours of sunlight.
You can measure nutrient levels with a conductivity meter. Cucumbers need between 1600 ppm and 2400 ppm of potassium, 3000 ppm to 4500 ppm of phosphorus, and 300 ppm to 400 ppm nitrogen.
Lettuce is one of the most common vegetables to find in hydroponic systems. You can grow it under artificial light, but make sure you place the lights between 10 and 20 inches above the leaves at all times. Lettuce likes more magnesium than calcium; use dolomite limestone if you want to boost both nutrients at the same time.
Maintain a pH level between 5.5 and 6.2 and a conductivity of around 2000 ppm to 2500 ppm for optimal results.
Kale is a very nutritious vegetable. If you grow kale hydroponically, make sure to provide it with plenty of potassium and nitrogen for big yields. It likes a pH level of 5.8 – 6.5 and conductivity between 3000 ppm to 4500 ppm for best results.
Radishes are very fast-growing vegetables that germinate in as few as five days. This makes them perfect for hydroponic systems because you can harvest them before they are fully mature. Radishes are not fussy about their nutrient requirements, so you can use general hydroponic fertilizer to achieve good results.
Be beans are fast-growing vegetables, which makes them perfect for hydroponic systems. They require plenty of magnesium and calcium in the soil, so use dolomite limestone to achieve this.
Make sure you measure nutrient levels daily; look for 150 ppm to 200 ppm nitrogen, 100 ppm to 150 ppm phosphorus, 300 ppm to 400 ppm potassium, and 100 to 150 ppm magnesium.
Spinach needs plenty of nitrogen and phosphorus for good results, but it should not be used as a primary source of these nutrients unless you add some fertilizer to the system. You want a pH level between 5.8 and 6.5 for best results, and take measurements frequently so you can maintain an optimal balance between all factors.
Celery is all about getting plenty of nitrogen and phosphorus for big yields. Use dolomite limestone to boost both nutrients simultaneously and aim for a pH level between 6.0 and 6.8 for best results.
Measure nutrient levels frequently; you want around 100 ppm to 150 ppm nitrogen, 200 ppm to 250 ppm phosphorus, and 200 ppm to 300 ppm potassium.
Peppers are high-yield vegetables that develop much better when adding humidity to the system. The ideal pH level is between 5.6 and 6.2, and you should pay attention to conductivity levels to make sure they stay above 2000 ppm.
Cabbage has a short growth cycle, but it is very demanding for calcium and potassium. Keep soil pH levels between 5.8 and 6.5, and pay close attention to your conductivity reading; aim for a level of around 2000 ppm or above.
Tomatoes are very high-yield vegetables, but they need a lot of heat and sun to grow big. If you have the luxury of growing tomatoes in a greenhouse, then go ahead and use them for your hydroponic system. However, if not, all you can do is place some heating lamps over your plants, so they get plenty of heat. Tomatoes also need a lot of potassium and nitrogen, so use dolomite limestone to boost both nutrients.
Measure conductivity frequently, and aim for a level of 3000 ppm or above for optimal results. You want a pH level between 5.8 and 6.5 as well, though tomatoes can tolerate levels as low as 5.5 or as high as 6.8, according to this hydroponics guide.
Cauliflower needs plenty of calcium and potassium to produce large heads. Use dolomite limestone to boost nutrients and measure the pH level frequently; make sure it stays above 5.8 for optimal results.
Corn is a fast-growing, high-yield crop that loves plenty of potassium and nitrogen. When growing corn hydroponically, ensure that you maintain a pH level between 5.7 and 6.0 while boosting the conductivity above 2000 ppm.
You can add general hydroponic fertilizer to boost the nutrients daily, but you should also add a calcium source.
Eggplant only needs a small amount of calcium and phosphorous to grow, so you can get away with using general hydroponic fertilizer. However, according to this hydroponics guide, the pH levels should be between 5.8 and 6.5. You can also use dolomite limestone to boost these nutrients and potassium levels daily.
Broccoli is a heavy feeder that needs potassium and nitrogen, requiring plenty of calcium and magnesium. Aim for a pH level between 5.8 and 6.2, and pay close attention to conductivity levels; aim for around 2000 ppm or above.
Onions come in as one of the lowest-demanding vegetables in hydroponic fertilizers. They do need plenty of potassium, though, so use dolomite limestone to boost the nutrient levels.
Measure pH and conductivity frequently, and aim for a level between 2000 ppm and 3000 ppm for optimal results. Keep the levels of nitrogen around 100 ppm to 150 ppm.
Leek is a nutrient-demanding vegetable that grows best in cooler climates. You can also use dolomite limestone to boost the nutrient levels and ensure that your pH level stays between 6.0 and 7.2.
Beets need plenty of calcium and magnesium, so add dolomite limestone to the system. Beetroots also need a lot of potassium and nitrogen; aim for around 100 ppm to 150 ppm nitrogen, 200 ppm to 250 ppm phosphorus, and 200 ppm to 300 ppm potassium.
Measure pH and conductivity frequently while adding a source of calcium at least once a week.
Chard is a moderate feeder that enjoys plenty of potassium, nitrogen, and calcium. Conditions for growth are similar to beets, so add dolomite limestone and measure the pH levels frequently.
Peas only need a small amount of potassium and nitrogen, so you can get away with using general hydroponic fertilizer. They do enjoy phosphorous and magnesium, though, so add dolomite limestone regularly.
According to this hydroponics guide, add calcium to your system every week or two; the pH level should stay between 6.2 and 7.0.
Squash is an incredibly nutrient-demanding vegetable, so pay attention to the levels of phosphorous and potassium in particular. General hydroponic fertilizer works fine for this crop, but frequent additions of dolomite/lime are also necessary. Be sure to monitor pH levels; they should be between 5.8 and 6.5.
Zucchini is a moderate feeder that only needs potassium, nitrogen, and calcium to grow. According to this hydroponics guide, the pH levels should be between 5.8 and 6.5, while the conductivity level should be somewhere above 2000 ppm. You can also use dolomite limestone regularly to boost potassium levels.
How to grow vegetables hydroponically: video
Many vegetables and herbs require the same levels of hydroponic nutrients, so you should be able to get away with using general hydroponics fertilizer. Pay close attention to how often you measure pH and conductivity levels while keeping an eye on the nutrient quantities.