Do plants cry? It may appear like your indoor plants are shedding tears when you see water drops on leaves, but they can form water droplets like outdoor plants. Water drops on plants can be caused by transpiration, dew, or guttation.
Transpiration, dewy situations, and guttation does not hurt your plants, but they can harm your furniture or floors. The easiest way to stop the water droplets: Cut back on how much you water your plants.
Causes of Water Drops on Plants
- Transpiration: Most of the time, water drops on plants are caused by transpiration, the plant's usual water exchange process.
- Dew: Surface moisture condenses on the plant due to temperature differences in the air and the plant.
- Guttation: The term for a plant that releases its excess water. Guttation is one way houseplants attempt to regulate their growing conditions independently. Guttation can occur when a plant has been overwatered or under stress, or the plant could be perfectly fine and want to balance its nutrients or minerals.
How Transpiration Causes Water Droplets
When houseplant leaves develop droplets of water on their tips, it is probably just transpiration as water moves through the plant and evaporates from its leaves, stem, and flowers. Water droplets on leaves are a natural occurrence, just like people sweating. When a plant is saturated, it needs to release the excess moisture, and it does it by transpiration through its leaves.
Leaves drip when they have as much moisture as they can hold. During humidity spikes, most plants will not need as much water as they usually would. You won't see a flood of water, just a droplet or two on the tips. The water will fall off or evaporate, and you won't see it happen again unless the situation repeats. Let your plants be your guide, and adjust the water you give them.
If you notice a pattern, cut back from weekly watering to every other week and monitor the plants to see if they still drip or if you have gone too far in the other direction and are now wilting between waterings. The amount of water a plant needs changes throughout the year.
What Causes Dew Droplets?
Water droplets will collect on the leaves if it's humid or dewy. You'll notice it generally occurs in the summer, especially if windows are open. Dew is caused by cooler air that can't hold as much water vapor as warmer air. As the temperature drops, the condensation rate exceeds the evaporation rate, and water droplets form.
The humidity during the day and the moisture in the air when the dew settles in the morning may be absorbed, to some degree, by plants' leaves.
Water Drips Caused by Guttation
Nine times out of 10, a plant normally expels water via transpiration, but sometimes, a plant may be experiencing guttation. Plants release water and nutrients from hydathodes or special pressure release valve cells on the margins or tips of leaf blades. Guttation releases droplets of xylem sap from the ends or edges of a plant's leaves. This sap is often mistaken for water, but it's water plus nutrients or minerals. Guttation is nature's way of restoring the balance between the plant's nutrients and water content.
This phenomenon often occurs at night because the stomata or regular pores used in transpiration are closed. The plant closes its stomata to preserve its water for photosynthesis during the day. Since transpiration can't occur at night, the plant developed the guttation process using hydathodes to relieve pressure when necessary. Even though water lost to guttation contains minerals and sugars, the losses don't affect the plant negatively.
So, even when you think you are doing everything right by your plants, they may have trouble adjusting. Sometimes they can adapt to conditions indoors, and sometimes they can't. In most cases, guttation will not harm a plant. However, in rare cases, bacteria can grow in guttation droplets and be pulled back into the leaf when the sun comes up, leading to disease infection, according to the Division of Plant Sciences, the University of Missouri.
Calla Lilies and Other Plants That Commonly Drip
Seedlings and younger plants experience guttation more than older, more established plants. While guttation can occur indoors with many vascular plants, grasses, and fungi, it is particularly common with calla lilies.
Guttation is usually a sign of an over-watered plant since the saturated roots pressure the rest of the plant. This pressure forces the plant to exude its excess moisture (and nutrients) in the form of sap. Cut back on watering, and your plant should stop releasing sap.
Other houseplants that experience guttation more than others include succulents like echeveria, jade plants, senecio, kalanchoe, monstera, dieffenbachia, ficus, philodendron, zz plants, and others.
Fruit and vegetable plants also guttate, including corn, tomatoes, potatoes, wheat, squash, cabbage, cucumber, strawberries, peppers, and grapes. Common shrubs and flowers that experience guttation at a higher rate are hydrangeas, hibiscus, roses, and impatiens.
Guttation. University of Missouri Environment Extension