Say goodbye to the mess—discover the best houseplants to grow in water and tips for thriving without soil!
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The nutrients for plants are usually provided through the use of a good soil, but what about growing plants in water? Growing plants in water, whether houseplants, outdoor plants or an indoor herb garden, is an interesting activity for the novice gardener (great for kids!), people with limited space, and those who are plant watering-challenged. This method for growing plants is not only low-maintenance, but also disease and pest resistant.
Growing plants in water without soil is most commonly done as a way to propagate a plant using cuttings. But there are plants that can grow in water alone, some of which are listed at the end of this article. Growing houseplants in water is also known as hydroponic farming, although when commercially grown in this manner, farmers use a more specific cocktail of water to liquid nutrition instead of soil.
Growing plants in water, also known as hydroponics, is an easy and fun way to enjoy houseplants without soil. All you need is a glass jar or vase, some water, and a cutting from your favorite plant However, without soil, plants don’t have access to the nutrients they need to thrive. That’s where fertilizers come in.
When using fertilizers for hydroponics, there are a few key things to keep in mind:
Types of Fertilizers for Hydroponics
There are two main types of fertilizers used for plants grown in water:
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Liquid fertilizers – These are soluble fertilizers that are mixed into the water. They provide an immediate nutrient boost but have to be reapplied frequently. Popular options include fish emulsion and seaweed extract.
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Slow release fertilizers – These provide a constant supply of nutrients over an extended period of time, Osmocote is a common slow release pellet fertilizer used in hydroponics
Nutrients Plants Need When Growing in Water
Plants need three main nutrients when grown hydroponically:
- Nitrogen (N) – For healthy, green growth
- Phosphorus (P) – For strong roots and flowers
- Potassium (K) – For disease resistance and sturdy stems
They also need smaller amounts of micronutrients like calcium magnesium, iron and zinc. A balanced fertilizer contains all of these in the proper ratios.
How Often to Fertilize
How often you need to fertilize depends on a few factors:
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Type of fertilizer – Liquid feeds may need reapplication every 1-2 weeks while slow release feeds can go 2-3 months between applications.
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Plant growth rate – Fast growing plants use up nutrients quickly and need more frequent feeding. Slow growers can go longer between fertilizing.
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Water changes – Fresh fertilizer should be applied after each water change, around every 2-4 weeks.
In general, fertilize at half the recommended strength every 2 weeks or with each water change. Watch for signs of nutrient deficiencies like yellowing leaves or slow growth and increase frequency as needed.
7 Best Fertilizers for Hydroponic Plants
Here are some of the best fertilizer options for nourishing plants grown in water:
1. Fish Emulsion
Made from fish byproducts, this organic liquid feed provides a quick dose of NPK, plus beneficial microbes. The fishy smell fades quickly. Use 1⁄4 strength weekly.
2. Seaweed Extract
Seaweed is a natural source of potassium, magnesium, iron, zinc and other trace elements. It’s especially good for promoting healthy roots and stress tolerance. Use every 2 weeks.
3. Compost Tea
Steeping finished compost in water creates a mild, nutrient-rich fertilizer. Compost tea also contains beneficial microorganisms. Brew a batch every 2-4 weeks.
4. Worm Castings Tea
Like compost tea, worm casting tea is filled with nutrients and good microbes. Brew up a batch using worm castings and use it to fertilize plants every 2-3 weeks.
5. Banana Water
Simply submerging banana peels in water creates a liquid fertilizer high in potassium and magnesium. Let peels soak for a day or two before using the water.
6. Epsom Salts
Dissolve a teaspoon of Epsom salts in water to provide magnesium and sulfur. This can help plants develop lush foliage and beautiful blooms. Use every 3-4 weeks.
7. Aquarium Water
Siphon water from a freshwater aquarium to give plants a dose of nitrogen and micronutrients. Make sure tank water tests safe before using.
Troubleshooting Nutrient Deficiencies
Here are some common nutrient deficiencies to look out for:
- Yellowing leaves – Nitrogen deficiency
- Spotted or curled leaves – Calcium deficiency
- Poor flowering/fruiting – Phosphorus deficiency
- Weak stems – Potassium deficiency
Target fertilizers to the specific nutrient needed or use a balanced, hydroponic blend to correct deficiencies.
Growing plants in water can be an incredibly rewarding process. Pay close attention to their nutritional needs by fertilizing regularly with hydroponic blends. This will keep plants thriving for months or even years without soil!
How to Propagate Plants in Water
Growing plants in water is often a method of propagation using clippings that can develop roots while submerged. To start new plants from existing plants, cut a 3-4 inch (8-10 cm) stem from the parent plant. When you make your cut, be sure to leave at least one node at the point where the leaf emerges from the stem, and some leaves at the end. Put the cutting in a clean container filled with fresh tap water. Make sure no leaves are submerged.
Place the cuttings in an area of bright but not direct sunlight and away from any drafts at a room temperature of around 70 F (21 C).Gardening tips, videos, info and more delivered right to your inbox!
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Change the water at least twice a week to keep it clean and oxygenated. Roots will generally appear within 3-4 weeks. When the roots are an inch or two (2.5 or 5 cm) long, remove the cutting from the water and plant it in a well-draining planting medium.
Caring for Plants Growing in Water
You can use pretty much any type of container, from vase to glass jar to old yogurt container. But clear or colored glass looks the prettiest and allows you to keep tabs on the root system as well as the cleanliness of the water.
Consider the possibility of removing the plant if the neck of your container is small so that youll need to break the plant to get it out. Most any type of waterproof receptacle will work except those made of copper, brass or lead. Metals may corrode when reacting to fertilizer and can cause plant damage.
Once you have picked the appropriate container, fill it three-quarters full with florist’s foam (the best bet), crumbled Styrofoam, gravel, pearl chips, pebbles, sand, marbles, beads or any similar material. Add a pinch of powdered or small piece of charcoal to keep the water clear and clean smelling.
The amount of light the plant gets will affect the quality of the water. Try to choose low-light plants to grow in water, and keep them in bright indirect light. If your plant needs direct sun, chances are high the water will become cloudy with bacteria that also thrive with sun.
A dark or opaque container will help to prevent algae formation. It won’t matter to the plant, however, which uses its leaves – not roots – to photosynthesize. If you do get algae, either remove the plant, clean the container thoroughly and replace the water and plant.
Change the water every 2 to 4 weeks, and fertilize your plant every 4 to 6 weeks. You can use a liquid fertilizer or one formulated for use on hydroponic plants. Use according to the manufacturer’s instructions.
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FAQ
What to feed plants that grow in water?
You can use a liquid fertilizer or one formulated for use on hydroponic plants. Use according to the manufacturer’s instructions.
What food plants can be grown in water?
- Cabbage
- Carrot
- Celery
- Green Onions
- Leeks
- Lemongrass
- Lettuce