Broadly speaking, plants need three things to survive: light, water, and a growing medium. The growing medium can include soil, peat moss, LECA, and even just plain old water. Growing your plants exclusively in water is possible as long as you fulfill a few simple requirements. If you stick to these easy-to-care-for plants that grow in water, you won’t need a complicated hydroponics setup.
Growing plants in water can be as simple as placing cuttings in a watertight vessel. However, if you want your plant to thrive, a little more work is involved:
Lighting Needs For Hydroponic Plants
To keep your plants healthy and thriving, you need to provide them with their necessary light requirements. Light is essential for photosynthesis, and without the right amount of light, the plant will not thrive. Plants that grow in water all require different amounts of light, so it’s best to check the light preferences for each specific variety you grow.
The Right Container Is Important
Just about any container (except metal which will corrode) will work for growing plants in water. Glass containers while attractive, are more susceptible to algae growth due to light exposure and stagnant water. One way to avoid this is to use an opaque container (in plastic, glass, or ceramic). An opaque container does not prevent algae growth, but it slows it down. You can also add a pinch of powdered charcoal or a few small pieces of charcoal to the water to help inhibit algae growth.
Fertilising Needs For Hydroponic Houseplants
While plants will easily root in plain water, they need food to survive and thrive. Typically, plants grown in water require lower strength fertilizer than those grow in soil. In general, you want to dilute a water-soluble fertilizer to a quarter strength, but this will also depend on the plant and the type of fertilizer you’re using.
The Right Water For Hydroponic Houseplants
Unchlorinated water is best for plants. Age tap water overnight at room temperature to remove chlorine. Most plants only need a monthly water change to stay healthy, but a lot depends on the type of vessel, the plant, and the amount of sunlight it gets. Over time, the water will evaporate from the container, so be sure to replenish the water weekly and completely change the water once it starts to look murky.
Plants That Do Well In Water
Any soft-stem herb will survive solely in water. It’s essential to cut it from the soft, green stem and not the woody stem for best results. Herbs with woody stems will survive, but the stem tends to get mushy before it roots. Take a cutting from a mature, healthy plant and place it in a sunny spot. Herbs need plenty of bright, indirect light to thrive.
Regrowing vegetable scraps such as lettuce, green onions, and carrot tops is a great way to reuse parts of the vegetable you would normally toss away in the trash. However, don’t expect a large harvest from them—regrowing scraps is mostly for fun. Keep about three inches of the bottom part of vegetables and place them in a shallow bowl of water. Your scraps will root and put out new growth from the centre.
This plant has to be the easiest to grow. All you need to do is add enough water to keep the roots covered. It doesn’t need fertiliser, but you can give it very diluted fertiliser monthly.
Pothos Or Money Plant
This easy-to-grow houseplant grows happily in water. Pothos produces plenty of auxin, a hormone in plants that regulates growth and helps stimulate root growth. If you mix pothos cuttings with other stems, it will speed up growth. As a vining plant with aerial roots, all these roots need is exposure to water to have a growth spurt. The same holds true for any vining plant, including monstera, English ivy, and hoyas.
Philodendrons have either a vining or upright growth habit. The vining varieties, including heartleaf, Brasil, and micans can be grown similarly to pothos in water. You will need to make sure you cut below a leaf node for the upright varieties such as pink princess, lemon lime, and birkin before placing them in water.
This colorful foliage plant roots quickly in water. Take a six-inch cutting and remove the leaves from the bottom four inches before placing it in water. Keep the cutting in a sunny spot and fertilise monthly for best results.
All types of begonia grow well in water, but rex and tuberous varieties do exceptionally well. As long as you take a healthy stem cutting with a node, they will root. It will take several weeks before you see any root development, be sure to change the water regularly and be patient.
The Chinese evergreen is a hardy plant that requires little attention, both in soil and out. Cut off a few inches of your Chinese evergreen plant. Ensure the cutting is long enough to have a couple of inches submerged underwater and some leaves above the waterline. Replenish the water as needed.
We hope this helps you get a little more adventurous in your gardening. Don’t be afraid to ask your friends or neighbours for cuttings of plants that you find attractive to try and propagate. Gardening on any scale (no matter how small) is a soothing and mentally relaxing activity and it’s something that literally anyone can master. All you need are some plant cutting, a window sill, water and some plastic or glass jars.