If you've been on your plant journey for a while and are an avid gardener, you may have heard of bottom watering plants and wondered how it differs from top watering. We want to differentiate between the two and tell you the pros and cons!
What is bottom watering?
Bottom water involves setting your plants in water (with drainage holes). The capillary action occurs as water slowly rises upwards throughout the base of the plant's soil despite gravitational force. The molecules adhere to soil particles and ascend via tiny air chambers rising to the soil line.
When and why to bottom water?
Remoisturizing a Dry Mix
There are a few reasons you may want to water plants from the top or bottom. If you've been away from home and didn't have a plant sitter and you return only to find that your plant's soil is receding from the pot you might want to bottom water.
Soil mixes with peat moss have a more challenging time remoisturizing after the peat moss has gotten completely dry. Soaking the roots (inside a grower pot or something with drainage) may be easier to get water to the roots this way. Add a wetting agent like dish soap to warm water. Mix it by adding tepid water to a gallon jug, and afterward, drop a 1/8th teaspoon of dish soap into the water and stir but not enough to cause suds.
Let it sit for 24 hours to evaporate any chlorine, then use this water to soak your plants from the bottom.
Add 1/8th teaspoon of dish soap to a gallon of water after filling to act as a wetting agent when the soil is extra dry.
The Peperomia leaves cover and hang over this container
If you have a plant whose leaves completely cover the top of the container and you can’t barely get a nozzle around the leaves without damaging them, then you might want to bottom water, especially if you struggle to see if your pkant needs more or less water. For example, Peperomia Frost and Rosso can be so flushed out and full that it's hard even to fit your plant meter prongs into the soil. But we recommend being extra careful and doing it anyway to check before watering. African violets can also be ones you may want to bottom water from time to time. Their leaves are fuzzy, and certain chemicals in the water can leave marks or brown the leaves if some are left on them.
Also, if leaves are lying on the topsoil, lift them off the soil. Brush them off and place some pebbles on the surface, so the leaves are not constantly lying on top of the moist soil. If not, the leaves will soak up moisture, and cause the leaves to discolor or rot.
Which Plants Like Bottom Watering?
Plants that naturally have consistent moisture in nature or bog plants would like base of plant bottom watering. Plants like Acorus, bamboo, calla lily, Chinese evergreen and Cyperus can handle constant saturation. Hence, this bottom-up watering method creates a natural environment for your plant.
Bottom watering seedlings is a better method, so the seeds don’t get dislodged by the force of the water coming from above. Just make sure that the water reaches the top of the soil, or the seedlings may not germinate.
Root Bound Plants
Additionally, if the plant's roots are massive or root bound, bottom watering your plant might be the best alternative until you repot your plant!
How to Bottom Water
Check the Moisture Level First
Before starting your watering chores, make sure to check the soil's moisture with one of our 3 in 1 plant meters to ensure it's really in need of water! So many "over love" their plants, and the meter prongs will give you a definite reading on whether it's time to water or not so you aren't asking "Does my plant need more or less water?"! So many plants have beat the odds of drowning with this little handy, dandy device!
Type of Water
When watering your plants, whether it be top watering or bottom watering, use clean, unused tap water that's been sitting out for at least 24 hours to let the chlorine evaporate. Some plants react to the chlorine, and browning edges appear around the leaves. You can also use tepid (room temperature) unsoftened, distilled, bottled, or rainwater.
Set a Timer
Next, get a bowl slightly bigger than your plant, and using the water we discussed, fill it up to 1/4 of the plant container sides from the base of the plant. Then, put a timer on and set it for five minutes. Then, see how long it takes for moisture to reach the top of your soil line. Write that time down so you'll know what to expect and schedule accordingly. Of course, different times of year may differ slightly depending on if it's outside and how dry it is.
If after 15-20 minutes the bottom watering is not reaching the top of the soil, you may have to supplement with a little top watering using the long neck of your watering can to slip under the leaves and finish the job.
Be sure not to take the roots and soil out of the grower pot and soak in water, or you'll have a mess! Please keep your plant baby in the grower pot with drainage holes or a permanent container with holes. After you finish watering, lift it out of the water bowl and let it thoroughly drain for at least 15 minutes in the sink before putting it back into its cachepot. If it has a drip tray, empty it of water and don't leave the roots sitting in the water, which may cause root rot!
Problems with bottom watering
Once a month, we recommend to flush your plant from the top down when watering to remove any salt buildup from fertilizer deposits. Bottom watering from the base of the plant can pull the salts back up into the roots, which show up as browning tips and edges on leaves.
Disease can spread through sharing water
Remember your mom telling you not to drink out of someone else’s cup or you’ll catch their cooties? Same goes for your plant babies! If you're tempted to bottom water all your plants in the bathtub at once, please don't. Unbeknownst to you, plant diseases or pests may be lurking in the soil away from the naked eye. If you dunk them all in the same water, all your plants may get the same cootie by spreading in the water! Eeeek! This action is especially true for new plants you bring into the home!
Can you overwater by bottom watering?
Bottom watering is okay for smaller 4–6-inch plants, but we don't recommend this for larger plants. The time it would take to soak the roots in a larger potted container and get the full capillary action to the top of the soil may be too long. Plus, it would take a larger bucket to do it in too!
Bottom watering plants is generally more time-consuming instead of top watering, simply because you must keep track of how long you've had your plant in the water trough and be careful not to soak it too long. Also, it's a slower process for the plants to uptake the water vs. top watering. Plants need oxygen and keeping them in water over 20 minutes can stress the plant. While the plant is soaking in water, it isn’t getting oxygen since the spaces are filling up with water as it moves upwards. On the other hand, aquatic plants can breathe under water, but terrestrial plants don’t have the same adaptation!
What is top watering?
Top watering is a natural way to water and mimics the rain coming down on the plant. You'll use a watering can and water the top surface around the pot's diameter. The water will run down throughout the soil and drain out the drainage holes in the bottom of the container.
How to topwater
For the most part, if you're using a 3 in 1 plant meter to check the moisture levels and a suitable watering container with a long narrow neck, you can get under the leaves of the pot and water well without splashing on the leaves. Ensure you water around the entire diameter of the plant container. You'll want only 10-20% of the water to drain out of the bottom of the planter. Sometimes it may take two rounds of watering. Water, then wait a few minutes, letting it drain. Then come back and water again to hit any spots that may have bypassed areas. If you're still not satisfied that your soil is not registering moisture, then add a wetting agent (a few drops of dish soap) to your watering can and mix with tepid water.
If you have spillover when you topwater, you may have the soil up to close to the top of the container. Remove the topsoil and leave at least 1/2 inch of space between the topsoil and the lip of the container while still covering the roots. You may have to repot if you don't have this much space.
Why top water?Potting Mixes Differ
Some plants don't wick water up from the base of the plant as well in potting mixes like orchid mix if it's a very loose structure. In this case, top watering is essential!
Flush Buildup Salts
As stated before, top watering will flush out a buildup of salts around the plant's roots. It also mimics nature's rainwater coming down from the sky! If your plant's leaves are not fuzzy and don't mind a bath, giving them a shower with your nozzle attached can knock the dust off your plants easier and more naturally than wiping with a cloth. Of course, if you can't get your oversized Monstera in the shower, then you'll have to resort to dusting her.
No Disease Spread
Top watering doesn't spread disease or get your plants intermingled with each other. Using the same water on another plant isn't a good idea. Each plant needs its own clean, tepid water to drink. So don't recycle another plant's drippings to use in other plants! No drinking from the same cup, please!
Top watering is quicker and gives you time to inspect your plant for diseases or pests, trim off dead or damaged leaves and take time with each plant personally. While your plant is draining, you can do these extra tidbits to ensure it's healthy!
Best Plants to Top Water
If you have a plant with shallow roots, top watering will be the best way to water the roots. Plants like epiphytes, succulents, Snake plants, Calathea, Aloe, more mature Maranta, Sedums, Kalanchoe, Begonias, African violets, and Pothos have shallow roots. If you prefer to bottom water these types, keep them in shallow containers so the wicking action can reach their roots or else supplement with top watering.
Keep a Consistent Watering Schedule!
Now you've got an overview of each watering method! Some like bottom watering, and some like top watering for a different reason! You can figure out which one your plant responds best and go with that method! The most important thing for your plant is to keep it on a consistent watering schedule, so he's not stressed-out in-between times.
What’s Wrong with My Plant?
For more information on indoor watering, read our summer watering schedule. Have you overwatered your indoor plant and never know if your plant needs more or less water? Then read the signs here. If your plant’s leaves are looking dry, find out the signs here. If you think you might have a pest or disease, find out more with Miss Debbie at our informational YouTube channel and keep watching our social media for plant care!