Rice is the staple food consumed worldwide. While cooking rice, we generally tend to clean it with water and drain the water. But have you ever wondered about using this leftover water? Can you use this water for plants? And, is rice water good for plants? Let’s find out!
Key Takeaways
- Rice water is good for indoor and garden plants as it is rich in nutrients and starch that help in plant growth and helpful bacterial reproduction.
- You can use both fresh and fermented rice water for plants. Read below to learn how to prepare rice water!
- It’s best to apply rice water sparingly to your plants and supplement them with other organic fertilizers as well.
- Adding rice water to plants helps protect them from harmful bacteria and diseases. For more important benefits and tips for using rice water on plants, read along!
What is Rice Water?
Rice water is the byproduct of rice and is derived from washing, soaking, or boiling rice. Once the rice is cooked/washed, you can strain the excess water and use it for your plants!
The cloudy suspension you get after washing the uncooked rice results from the starch content and other minerals in the rice.
The following table shows the nutrient percentage that gets leached in the rice water.
| Nutrients | Percentage |
| Protein | 7% |
| Crude fiber | 30% |
| Thiamine | 59% |
| Riboflavin | 26% |
| Niacin | 60% |
| Calcium | 26% |
| Phosphorous | 47% |
| Iron | 47% |
| Zinc | 11% |
| Magnesium | 70% |
| Potassium | 41% |
These significant amounts of nutrients make rice water an excellent source of liquid plant fertilizer. Moreover, the research shows that rice water has auxins and gibberellin hormones that help plant growth.
However, the presence of these nutrients varies from varieties of rice, sources of rice, and washing intensity.
How to Prepare Rice Water
Preparing rice water is an easy task. You can make rice water for plants by either soaking or boiling the rice in water or by fermenting the rice water.
1. Making Fresh Rice Water from Soaking:
- Add rice to a small bowl and add 2-3 cups of water.
- Rinse rice grains thoroughly and leave them to soak for 30-45 minutes.
- Now stir the rice and strain the water into a bowl. Use this rice water for plants.
2. Making Fresh Rice Water by Boiling:
- First, rinse the rice grains and discard this water. (You can use this washed rice water as well for your plants)
- Then fill the pot halfway with water and bring it to a boil.
- Add the rice and let it boil for 30-45 minutes.
- When the rice is done, strain it and collect the water. Use this boiled rice water to feed your plants essential nutrients.
2. How to Make Fermented Rice Water
- Fill a sealed glass container halfway with rice water.
- Mix 1 tablespoon of sugar in it.
- Add four tablespoons of milk and give it a quick mix.
- Close the jar’s lid and let the mixture sit for 3-4 days.
- Once the water gets fermented, it becomes a translucent or opaque mixture, indicating that fermentation is done.
This fermented rice water promotes the growth of lactobacilli and helps increase crop yield.
How to Use Rice Water for Plants
Rice water is effective on indoor and garden plants, but its application may vary. It can be used after dilution once every two weeks, depending on the water needs of the plant.
For using rice water, you can go with different methods based on the type of plant you are supplementing.
- Misting: In misting, the diluted water is poured into a spray bottle and is misted over the plants. You can also use a vaporizer for this. This method is generally used to water drought plants with minimal water needs, like succulents.
- Bottom Watering: This method is also called immersion irrigation. The rice water is poured into a wide dish or tray, and the planter is placed on the dish. The water moves up the plant through capillary action via the pot drainage holes, preventing overwatering.
- Soil Application: Soil application is simply pouring rice water into the soil. Some of the indoor plants and garden plants are watered using this popular method.
The best time to apply rice water is in the seedling stage when the plant starts its growth cycle. This is the phase when plants highly require water and nutrients to increase crop yield.
How the Contents of Rice Water Benefit Plants
By now, we know that rice water is useful to plants. But how exactly? Let’s see how rice water works to keep the plants healthy.
- Rice water has vital nutrients like nitrogen, phosphorous, and potassium which aid plant growth.
- The abundance of starch in rice water protects plants from diseases and pathogens and keeps them green and healthy.
- The carbohydrates get stored in the plant cell membrane and help in the fermentation and growth of lactobacilli in the soil. These bacteria feed the mycorrhiza, which aids in nitrogen fixation in the soil and strengthens plant roots.
- The rhizosphere has increased bacteria that help plants in photosynthesis.
- The carbohydrates contain hydrogen, oxygen, nitrogen, and carbon, which help bacteria break down the organic matter into vital nutrients.
Benefits of Using Rice Water for Plants
Rice water has a multitude of benefits both for humans and plants. In plants, it can be used as a natural fertilizer, pesticide, and source of irrigation that boosts plant growth!
Here are a few benefits of rice water for your plants that you need to know before using it.
- Rice water promotes vegetative growth and protects photosynthetic tissues in plants.
- It protects plants from pests and diseases by providing plant nutrients.
- When used for irrigation, rice water can reduce the use of chemicals like NPK fertilizer, thereby preventing environmental pollution and groundwater contamination.
- Rice water is an easily available and cheap source of natural fertilizer.
- Using rice water for plants helps us repurpose kitchen waste and save water usage.
- Rice water prevents the burns caused to plants while applying inorganic fertilizers.
- Rice water has a slightly alkaline pH and helps the plants absorb the nutrients.
Risks of Using Rice Water for Plants
Although using rice water is beneficial for plants, it comes with some severe concerns. Below are a few risks you must know before feeding your plants with rice water.
- If rice water is used excessively, it might attract harmful bacteria and fungi. This may harm beneficial microbes in the rhizosphere and cause a severe effect on the plants.
- If rice water is used in orchids, the carbohydrates can harden the soil, attract pests or cause abiotic stress.
- Rice water ferments at a high temperature in the soil and accelerates the decomposition of moss and bark. This might cause root rot or some fungal issues in orchids.
- Rice water alone cannot fulfill the nutrient needs of the plant. You need to supply your plants with organic fertilizers, compost, or NPK fertilizer at least once a year.
Precautions to Take While Using Rice Water for Plants
Rice water is great for plants, but it has some ill effects too. So, here are some precautions you must take while using rice water:
- Do not add salt or other ingredients to the water when boiling rice. Adding salt will nullify all the benefits of using rice water for plants.
- Water should be at room temperature so that it doesn’t harm soil microbes.
- Use the bottom watering method or misting to prevent standing water and drainage problems.
- Use rice water at the limit as overwatering may cause root rot.
- Use fresh rice water to irrigate your plants. However, using stored or fermented rice water once a month is acceptable.
- Avoid using scented rice as it might contain some harmful additives. You can also make rice water from organic rice varieties for the better growth of plants.
- Dilute the rice water before using it on your plants. (You can use rice water and tap water in the ratio of 1:2 or 1:3 in general)
- Start applying the rice water in a small quantity, and you can increase the dose eventually.
Is Rice Water a Good Fertilizer?
Rice water is rich in starch and contains trace amounts of NPK. The carbohydrates and other nutrients in starch are beneficial for the soil microbes and help nourish the plants.
A study shows that rice water increases plant height and strengthens the roots and leaves. This makes it one of the best organic fertilizers to use for succulents, indoor plants, and garden plants.
But note that some fruit trees and other plants need NPK fertilizers once a year as the nutrients alone in rice water will not be enough for their growth.
Is Rice Water a Good Pesticide?
Yes, fermented rice water acts as a pesticide to deter pests like spiders, ants, lizards, and snakes from your garden.
Fermentation of rice water creates a sour-alcohol-like odor that irritates common plant insects. So, these pests will not breed on your plants if supplemented with fermented water.
Using Rice Water for Succulents
Diluted rice water can be used for succulents. As succulents generally grow in drought conditions, they require dry, aerated soil. So rice water should be misted in this case.
Succulents need modest amounts of nutrients. So, providing them with rice water in the early hours of the day or the evening would help them give beautiful blooms.
Mist the succulents with rice water during the normal watering process to give them the best benefits and avoid overwatering.
Simply dilute the rice water with tap water (1 part rice water and three parts tap water) and fill it in a clean spray bottle before spraying it on the leaves.
Plants that Benefit the Most from Rice Water
Research conducted by the Agriculture Faculty in Malaysia states that rice water benefits most indoor and garden plants. It helps increase the growth of vegetable crops like spinach, tomato, mustard, eggplant, lettuce, and Pak Choy.
Some studies also show that when rice water is used in rose plants, the number of flowers and the size of their blooms tend to increase.
Also, some indoor plants like the Chinese money plant, snake plant, aloe vera, lucky bamboo, and succulents show positive growth when fed with rice water.
How long can rice water be stored to use for plants?
Rice water lasts for 3-4 days if kept open at room temperature. If it is preserved in the fridge, it can last up to 5-7 days.
How often do you use rice water on plants?
Rice water can be used once every two weeks and is ideal for plants in the seedling stage. Avoid using rice water regularly, as the carbohydrates may harden the soil and attract harmful microbes.
Is Rice water good for Succulents?
Yes, rice water is good for succulents as they need moderate water and nutrients. The rice water can provide these nutrients to the succulents, keeping them healthy and booming. Remember to mist the succulents with diluted rice water.
Is rice water good for houseplants?
Rice water is beneficial to houseplants since it provides them with important nutrients. To make nutrients available fast and avoid overwatering, use an immersion or bottom watering method.
Can you water plants with cooking water?
Yes, cooking water has extracted nutrients from vegetables or cereals. Hence, it provides plants with available nutrients and reduces the need for synthetic fertilizers. But you can only use this water unless it is not seasoned with salt or other ingredients. You can use cooked rice water, cooked vegetable water, or eggshell water for your plants.
Is rice water good for compost?
Yes, rice water is an excellent ingredient for compost as it keeps the compost pile moist and adds essential nutrients to it. Rice water helps the microbes in the compost pile break down food. It becomes a nutrient-rich starter for composting creatures and reduces the need for chemical fertilizers.
What are the alternatives to rice water to supplement the plants?
In addition to rice water, you can feed your plants coconut water, white vinegar, potato water, compost tea, worm casting tea, seaweed tea, green tea, banana peel water, eggshell water, nettle tea, and dandelion tea.
Rice water is rich in vitamins and minerals and can supplement plants with nutrients when used along with organic fertilizers. So, next time you cook rice, don’t forget to make nutritious rice water for your plants.
