Bottom watering plants is an effective watering technique where the plant is placed in a bowl of water to let the soil soak up water from the bottom like a sponge.
This method helps prevent overwatering, promotes healthy root growth, and reduces the risk of fungal diseases, making it a beneficial practice for houseplants.
Watering Plants from the Bottom
Watering your plants the right way is the most important thing in plant care. Improper watering is the most common cause of plants not surviving in our homes.
Usually, we water our plants from the top, and most of the time that is perfectly fine to do. But in some cases, it can be better to water from the bottom. You don’t even need a watering can!
What is Bottom Watering?
Bottom watering your plants is literally watering them from the bottom instead of from the top. Some people call it reverse watering, which is the same.
The gist is that you place your plant in a bowl or cachepot with water to let it soak up water through the drainage holes on the bottom.
Bottom watering doesn’t completely replace watering from the top, but it is a very useful watering method to know.
Wick watering is not the same as bottom watering. To wick water, you use a piece of cotton string or a strip of fabric as a “wick” to soak up water from a water-filled container sending the water to the soil of nearby plants.
This way of watering can be very useful if you need to water your plants while away on vacation. It is quite simple to set up a self-watering system to wick water your plants in your absence.
7 Benefits of Bottom Watering Plants
If someone tells you bottom watering is good because it prevents overwatering since the plant will take as much water as it needs, know that that is not actually true.
It is the soil that takes up the water. And the soil takes up as much water as it can.
Now that is out of the way, there are a number of real benefits to watering plants from the bottom.
- If a plant is very underwatered, the soil can be dehydrated so much that it doesn’t absorb any water anymore. It will simply run right through the pot, never saturating the soil. This is known as “hydrophobic soil”. Bottom watering will help to saturate the soil entirely.
- Bottom watering also evenly distributes water throughout the soil. More so than top watering does. Watering from the top can leave certain dry spots in the soil.
- Watering from the bottom encourages stronger and better root growth. The roots will grow and reach to access the water below.
- Bottom watering can prevent leaf or crown rot by not having water pooled up in the crown of plants like echeverias, snake plants, and other succulents.
- Many plants are sensitive to water on their leaves. Hard water can cause water marks on the leaves. No water will get on the leaves if those plants are watered from the bottom.
- If fungus gnats are bothering your plants, bottom watering can help prevent those pests. Dry top soil prevents the bugs from laying their eggs and hatching.
- Watering from the bottom is also just convenient. Place the pot in water and wait. Capillary action will do all the work.
Save time by watering multiple plants from the bottom all at once. Place them all together in the sink or a large container. Bottom water large plants in the bathtub.
Which Plants Like Bottom Watering
Basically, all plants can be watered from the bottom as long as they are in a pot with drainage holes on the bottom. They should have these anyway, even if you only water from the top.
Drainage holes allow excess water to drain out of the bottom. Water stuck inside can drown the roots. If roots rot, they lose the ability to absorb water and can’t supply any water to the plant.
Moisture-loving plants like ferns, caladiums, prayer plants, and windowsill herbs are great candidates to bottom water.
Carnivorous plants like venus flytraps and Sarracenia pitcher plants need continuously moist soil. Place them in shallow, water-filled containers and basically bottom water them constantly.
Plants like African violets and the Iron cross Begonia don’t like to get water on their leaves. So bottom watering is definitely an appropriate way to water them.
Some plants grow in a way that the soil is hard to reach, even with a watering can with a long spout. Bottom water creeping plants like the pilea glauca or Tradescantia plants and large succulents in small pots to avoid getting water in their crowns.
Further reading – How and when to water succulents.
How to Water Plants from the Bottom
- Check if the plant needs water. Read up on how to water indoor plants to learn to tell if it’s time to water or not.
- Take a shallow bowl or cachepot that is a bit wider than the plant’s pot. Fill with room-temperature water about halfway up the outside of the pot.
- Place your plant pot to soak up the water through the drainage holes on the bottom of the pot.
- Check the surface every fifteen minutes or so to see if the soil has absorbed enough water.
- Remove the plant when the top of the soil feels moist. That is when the soil is saturated evenly.
- Remove any excess water that remains when your plant is done soaking.
Refill the bowl if it empties before the soil is saturated. If the soil is very dry you might have to refill the bowl a few times.
Possible Salt Buildup Problem
A common problem with bottom watering is the buildup of excess salt on the soil or sides of clay pots. This happens over time when tap water is used instead of distilled or filtered water.
The salt buildup shows up as a white crust on the soil surface or on the outside of clay pots.
You can fix this by watering from the top once every four to six weeks or so. Doing this will flush out the salt buildup.
Bottom Feeding Plants
You can feed the plants when you bottom water by adding a diluted dose of liquid fertilizer.
Similar to top watering your plants, fertilize once a month during spring and summer. Don’t fertilize in winter when plants go into dormancy and growth slows down.
How Long Should you Bottom Water
How long you should bottom water ranges from about 30 minutes to a few hours. It depends on the size of the pot, type of pot (plastic or clay), how dry the soil is, the type of potting medium, and the density of the root ball.
Larger plants might need a few hours, whereas small plants in smaller pots will take considerably less time.
Some people even bottom water their plants overnight. I prefer not to, because I like to check in on the moisture level and if the bowl needs to be refilled mid-way through.
If it’s not working and water isn’t reaching the top, it is probably that the water level in the bowl or tray is too low. Add more water and try again.
