Bottom Watering vs Top Watering: The Facts


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Water makes up 85-90% of a plant’s weight. Bottom and top watering both help carry essential nutrients and minerals from the soil to the cells, making the plant healthier and stronger.

Bottom watering plants keep the soil uniformly moist so the entire root structure gets watered, however, the downside to this is salt build up over time. Top watering encourages the presence of fungus and gnats while the water can be channeled out of the soil, not being able to reach the entire root structure. However, using them together can eliminate these problems.

Garden soil requires about one inch of water every seven days and the soil structure should be kept healthy to enable the plant to absorb water efficiently. 

Plants in a hot, humid environment require two inches of water per week. Regularly applying water to your house plants can avoid many problems, such as slow growth and dryness. 

There are two broad categories of watering your houseplants: bottom watering and top watering. In today’s article, I will differentiate between these two and explain the reasoning for using both methods. 

Bottom watering and Top Watering

What is Bottom Watering?

Unlike top watering, bottom watering is an effective method to apply water to your house plants from the bottom up. 

It makes the root stronger and allows them to grow directly toward the moisture. Research shows that moisture in the potting soil reaches the bottom and nourishes the roots. 

Bottom watering allows your house plants to absorb sufficient water without drenching their foliage and overwatering. With this method, you can ensure the roots get enough water, which is sometimes not possible with top watering. 

Add water to the saucer of the pot and let it sit. 

Add more water when required, until you get wet soil. Some homeowners use a large container to hold the planter and fill it halfway with water. 

Remove the water if the soil is moisture under the surface after 10-15 minutes. 

If the soil feels dry, give it another 10-15 minutes or more time to get moisture to the top. 

When you top-water your plants, the soil may not be getting the water it requires if there are channels or gaps within the soil structure. However, leaving the water in the drainage plate can lead to root rot.

However, bottom watering is an effective method that enables you to avoid this problem. 

For example, you can take out the pot from the plate and put it back when needed. That way, you prevent overwatering the plants. 

See our complete guide for bottom watering plants which gives easy-to-understand details with step-by-step instructions from our years of experience.

Bottom watering plants infographic

Interested in bottom watering trays? I have found some cost-effective and durable trays which worked well for all my plants. You can find them by clicking here.

10 Plant Growing Trays

Advantages of Bottom Watering

Bottom watering is a practical, healthy, and sophisticated method, which allows seedlings to receive moisture into the soil from the bottom up. 

Research has highlighted various benefits of bottom watering. For instance, it does not displace fragile seedlings during their growth and allows the soil to absorb moisture more uniformly. 

Bottom watering keeps the soil moist consistently, enabling the seedlings to get enough water. That way, you can prevent seedlings from overwatering. 

It also saves you time if you are a busy person because you won’t water them frequently. Besides, bottom watering helps your plants to develop healthier and stronger roots. 

The reason is that the roots grow down toward the water source. Bottom watering is a healthy way to water your plants, preventing you from splashing water on the leaves. 

On the other hand, top watering can spread diseases from plant to plant because it often involves splashing water on the leaves. 

If you want to keep the maximum moisture at the bottom, you should follow the bottom watering method.

It allows the roots to grow faster and maintain a healthier root system. 

Some plants do not require their leaves to stay wet. Top watering can make the leaves drop off or develop yellow spots. In such a situation, you should consider bottom watering, which is a much safer method. 

Top watering also provides a favorable environment for pests. The top surface of the soil damp in water increases the pests’ growth, which eventually leads to damaged leaves. 

See how bottom watering prevents gnats.

In contrast, bottom watering keeps the surface dry, allowing the leaves to flourish by decreasing pests’ development. 

When applying water to my plants, I use a cost-effective and durable watering can that I got on amazon which makes watering fun and easy without any spillage.
You can find it by clicking here.

MyLifeUNIT Plastic Watering Can green
Plant absorbing water from bottom watering

Disadvantages of Bottom Watering

There are several downsides of bottom watering besides its many benefits. Bottom watering can lead to the accumulation of minerals and salts in the soil, weakening the roots and causing root burns. 

Many people use tap water for their houseplants, which is relatively hard in nature. 

Experts recommend applying water from the top every three months to prevent salt and mineral deposit, especially if you use tap water. 

Fertilization works much better with top watering than bottom watering. However, you can add fertilizer when bottom watering, but remember to switch it up to prevent mineral buildup.

The buildup of salt and minerals can damage your plants, preventing them from absorbing the required water. 

All this leads to burning of root tips, stunt growth, and rotting. Plant cells have membranes, which allow water to enter while keeping larger salts out.

Bottom watering deprives roots of getting enough oxygen as it fills the spaces with water as it moves upwards in the soil.

Too much water from bottom watering will kill the roots and make your plants more vulnerable to root rot, making the roots mushy and break off easily. 

Bottom watering is somewhat problematic for larger plants. If you have larger plants at home, they will take a lot of time to absorb enough moisture. 

The problem worsens if your plants are in terracotta pots. That’s why you have to create the right balance between the bottom and top watering your large plants. 

Larger plants can also be very heavy to handle and any mishaps can lead to damage to both you and the plant.

Bottom watering My plant

Plants that Bottom Watering Works Best with

Bottom watering is an excellent technique used for small and medium-sized plants. The method is not suitable for heavy and tall plants. 

For example, if you have African violets and apply water from the top, they will develop discolored leaves. 

Some root-bound plants do not allow the soil to soak enough moisture, but you can avoid this problem through bottom watering. 

Likewise, if you have watermelon peperomia, you can use the bottom watering technique because they do not like wet leaves such as piggyback plants.

Plants that Like Bottom Watering. 

  • Dragon tree, 
  • Fiddle leaf fig, 
  • Pothos, yucca, 
  • Cissus, 
  • Spider plant,
  • Ponytail 

How does Bottom Watering Affect Root Development?

Roots play a crucial role in plant development and growth by providing an interface for water and nutrient absorption. 

Research highlights that roots provide the anchor required to keep the plant firm and in place. 

More practically, they take up water, oxygen, and minerals from the soil and transport them to the leaves. The movement of water and nutrients interact with sunlight to trigger the process of photosynthesis. 

The purpose is to produce sugars and energy for the plant. 

The question is: how bottom watering affects root development? 

Bottom watering provides uniform moisture to the roots, but it does not eliminate the mineral and salt deposits present on the top of the soil. 

You must monitor the water absorption when using this approach for at least 30 minutes. If the soil does not let out the excess water, it can suffer from oxygen deficiency. 

As a result, the roots will not get enough oxygen, causing them to suffocate or rot. 

On the other hand, bottom watering is an effective method for seedlings. It prevents seedlings from getting damaged by streams of water. 

Bottom water encourages root development, especially for plants like African violets that don’t like wet leaves. 

Moreover, bottom watering allows the roots to spread out and stay healthier. It provides the plant’s roots with enough moisture, allowing them to grow toward the pot’s bottom. 

How to Bottom Water Plants?

Bottom watering is an essential method that requires you to place a potted plant in a sink or tub with a few inches of water in it. 

The planter contains drainage holes, which enable the soil to absorb the water for some time without oversaturation. 

Bear in mind that your planter should have at least one drainage hole when applying water from the bottom. 

If it does not have a hole, you won’t be able to get water into the planter. Here are the steps to bottom water your indoor plant. Continue reading! 

Fill Your Container or Sink with Water 

Fill the container or sink with sufficient water so that it reaches the bottom of the soil. You won’t face any problems with the water level if your planter is filled with soil. 

If your planter has drainage rock at the bottom, make sure you keep the water levels slightly higher than the stones. The purpose is to allow water to reach the soil.

Remember, each type of soil has its own degree of water absorption. For example, if you use cactus soil with more rock and perlite, it won’t absorb enough water. 

Therefore, you have to fill enough water in the container or sink to allow the plant to soak in the required moisture. Not putting enough water means underwatering your plant. 

Place the Plant in the Water 

Once you have filled the container with the water, it is time to place your plants in it. Avoid using a grow pot or container with dried soil. 

Otherwise, the plant will start floating in the water and cause problems. 

Your plant must sit straight in the water to avoid complications. If you put your plant with dried soil in the pot, it may float and tip over, creating a lot of mess. Therefore, you have to be very careful in this regard. 

Keep the Plant in Water for 10 Minutes 

Let your plant stay in the container for at least 10 minutes. Check the soil after 10 minutes for moisture levels. 

If the soil is moist enough from bottom to top, then everything is going well.

Most often, the tip-top of the soil does not get wet but just a little moist. This is normal.

After the soil has received enough water, it is time to let the excess water out of the container. Make sure you place the plant on a dry surface for a few minutes to drain out the water. 

How to Bottom Water a Large Plant?

Although bottom watering is an effective method for small to medium plants, you can use it for a large plant. 

However, time is an important aspect you need to consider when watering your large plant. 

Keep in mind that the size of your plant will determine the amount of water it needs. If your plant is in a small pot, it will absorb water more quickly than a larger pot and therefore less time is required for watering.

Before watering your large plant, make sure you check the moisture levels. You can use a specialized gauge or push your finger into the soil to check moisture levels. 

Make sure you push your finger between the container’s wall and the plant’s stem. Push down to the second knuckle and if you feel the soil is dry, start watering the plant. 

When it comes to bottom watering a large plant, use a large container to hold the planter. Fill the container halfway with filtered or distilled water. 

Avoid using tap water because it contains higher levels of chlorine, which can damage your plant. 

After placing the planter in the sink or container, leave it for at least 10-15 minutes or depending on the plant’s requirements. 

Recheck the moisture level to see if enough water has been absorbed. If it is still dry, leave the planter in the container for 20 minutes or longer. The purpose is to allow the soil to soak enough water. 

See our article on how long should soil stay wet after watering.

Although bottom watering will keep the plant’s roots moist, it won’t wash away the deposited salts and minerals. To fix this problem, apply water to the top of the soil to get rid of accumulated salts and minerals. 

How Long Does Bottom Watering take?

The duration of bottom watering depends on several factors, such as the plant’s type, size, soil condition, and type of pot.

However, the general rule of thumb is to place the plant in a container with water that reaches 1 to 1.5 inches above the bottom of the pot for about 10-15 minutes.

Check the soil after 10 minutes and if the soil is still dry, increase the duration to 20 minutes. That way, you can accurately bottom water your plant. 

Don’t leave your plant for more than the standard 10-15 minutes to prevent overwatering. 

Places to Bottom Water Plants

Bottom watering is a specialized technique to keep the soil moist for your small and medium-sized plants. 

Many people ask about places to bottom water their plants. There are various places where you can bottom water your plants, such as the bathroom, bedroom, living room, etc. 

For example, if you have Kimberly Queen Fern, you can bottom water them in the bathroom. 

The plant loves humidity and soaks up polluted air

These plants absorb airborne toxins found in drywall and paint. Because snake plants require low light and maintenance, you can apply water from the bottom while keeping them where they are much needed.

If you have spider plants, you can keep them at the door. These plants work well with bottom watering. Avoid watering them in the bathroom or any other areas with low light and high moisture. 

fish food as fertilizer

How to fertilize when bottom watering

It is crucial to fertilize your plants if the soil does not provide enough nutrients for their optimal growth. Fertilizers play a pivotal role in nourishing the plant, leading to its proper growth and development. 

How to fertilize a plant when using the bottom watering approach?  You can add a water-soluble fertilizer with the water at least once a month when bottom watering your plant. 

Make sure you add a small amount of fertilizer. For instance, you should add half of the recommended amount per gallon of water if you use inorganic fertilizer. 

Moreover, if you have African violets or any other indoor plant that goes best with bottom watering, you need a 20-20-20 fertilizer solution. 

Add ¼ teaspoon of the fertilizer to one gallon of water. The solution works better if the plant grows under artificial light. 

If the plant grows under natural light, but does not get direct sunlight, I recommend adding 1/8 teaspoon of the fertilizer per one gallon of water. 

Some plants take advantage of the resting period, especially in the winter season. That’s why you must not fertilize the plant until new growth occurs.

Final Words 

Both top watering and bottom watering have advantages and disadvantages. Some plants prefer top watering, while others work well with bottom watering. 

Even if you use the bottom watering method, make sure you follow the rules and protocols to avoid complications and damages to the plant. 

JayLea

JayLea has a passion for plants and has been gardening since 2015. He has valuable knowledge about gardening and houseplant care and can answer everyday practical questions that every plant owner has.

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