White Crystals on Plant Leaves? Here’s Why and How to Fix It

It’s every houseplant owner’s nightmare when something unexpected happens to their plants, as there are plenty of things that can go wrong during plant care and cause a significant problem.

For this reason, observing the symptoms and identifying the cause as early as possible is the best thing you can do to ensure that your plant stays healthy.

White crystals appearing on the leaves of your plants is one of those symptoms that tell you vital information about issues your plant may be facing and one that you shouldn’t ignore.

So, what causes white crystals on plant leaves?

The white crystals on the leaves of your plant are a result of guttation, which is a process where the plant forces excess water from the roots to the leaves during nighttime. When water makes its way out of the leaves, it eventually evaporates and can leave behind white crystals made of minerals.

That being said, guttation itself isn’t necessarily a bad thing and only is harmful in certain situations caused by improper plant care.

What Is Guttation and How Does It Cause White Crystals?

As we have mentioned earlier, guttation is something a plant does to get rid of water that it absorbed despite not needing it.

When nighttime comes and causes the stomata of the plants to close, transpiration also stops, and the plant requires to get rid of the excess water, which is where guttation comes in.

The guttation process starts with the plant pushing the excess water from its roots to the leaves where hydathodes reside.

Unlike stomata, hydathodes are permanently open, which allows the plant to exude water even at nighttime.

When water makes its way to where hydathodes are, it’s slowly pushed out to the surface of the leaves, and the guttation process ends.

The water drops stay on the leaves until they evaporate, leaving mineral deposits behind. When a large amount of these minerals accumulate on the leaves in a relatively short time, they become noticeable in the form of white crystals.

While every healthy plant goes through guttation in times where transpiration isn’t possible, such as nighttime or days where humidity is too high, observing the formation of white crystals on leaves after guttation often points us towards the direction of improper watering or fertilizing.

Errors in watering and fertilizing can either cause guttation to happen way too frequently or load the water up with way too many minerals, with both scenarios causing white crystals to appear on the leaves.

How to Prevent White Crystals on Plant Leaves from Coming Back?

Fortunately, with slight changes in watering and fertilizing habits, you can prevent the white crystals from coming back ever again.

  1. Switch to soft water. Tap water is known to contain a lot of minerals that could very well be the cause behind the formation of white crystals, especially if you live in an area where the water is hard. If you have the option, collecting rainwater can be a great source of water for your plants, but if you don’t, bottled water is an equally great choice besides the fact that it’s more expensive. Water is the lifeblood of your plants, and ensuring that they get the best water possible is one of the biggest favors you can do for them.
  2. Water your plants in the morning. Watering in the morning will allow your plants to have enough time to process all the water through transpiration, which is the way it should be. If you water your plants too close to the nighttime, they might not get enough time until the stomata close, meaning that the water would have to be disposed of through the means of guttation. When this happens too frequently, it can cause the dreaded white crystals to form on the leaves of your plants. Unrelated to the crystals, the soil staying wet overnight can also make room for a variety of different problems such as fungal growth and root rot.
  3. Don’t overhead water too frequently. Overhead watering now and then is necessary to ensure that the foliage stays clean, but overdoing it can also be the reason behind the formation of white crystals due to water drops drying on the leaves. Frequent overhead watering can also cause fungal infection in some plants, so it’s best to be careful.
  4. Check for signs of overwatering. Overwatering is one of the primary reasons behind guttation and is also quite harmful to your plants for a wide variety of different reasons. Before watering your plant for the next time, try to feel the soil by inserting your finger into it. If it’s still wet, you can skip watering that plant until the soil becomes drier. Checking the soil is always the best way to understand whether a plant requires watering or not, as using a set schedule can easily cause under or overwatering due to changes in external conditions.
  5. Check for signs of overfertilizing. As overfertilizing causes the soil to have a lot more minerals than what’s required, white crystals can also appear on the leaves of your plant as a result of overfertilization. Overfertilizing is a serious problem that usually comes with more symptoms such as slow growth, dried and yellowing leaves, and wilting, so ensure that you treat your plant appropriately if some of these symptoms are also present.

How to Get Rid of White Crystals on Plant Leaves?

Alongside taking the necessary steps for preventing white crystals from appearing, cleaning them off the leaves of your plant is also an important step of the process.

Fortunately, this step is rather easy compared to finding out what caused these crystals to appear in the first place and preventing them from coming back.

To get rid of the white crystals, you can wipe the leaves with the help of warm water and cotton buds or a microfiber towel. While water should be enough to get the crystals off on most occasions, you can also mix a small amount of soap with the water if you are having trouble.

As crystals staying on the leaves for a long enough time can cause damage to the leaves by causing burns on the spots they are stuck on, wiping the crystals off the leaves as soon as possible is the best thing to do to ensure that leaf damage doesn’t occur.

Wrapping Up

As the appearance of these crystals is related to improper plant care, make sure that you give your plant a thorough check-up as soon as you notice them find out what you need to fix.

While the crystals can be caused by something simple as using water that is too hard, it also could point to a severe issue such as overwatering or overfertilizing.

The best course of action in such a situation is to take the necessary steps for identifying the cause of the problem as soon as possible while keeping your plant healthy by getting the crystals off with frequent cleaning.