What Are Black Tips on Leaves on Outdoor Plants?

If your outdoor plants are showing black tips on leaves, it could be a sign of root rot. You may be able to save your plant by pruning the dead tips, leaving healthy foliage behind.

However, you should also look for other causes of the leaf discoloration, such as disease, temperature stress, and fungus. Identifying these issues is key to avoiding their spread.

Humidity

Most gardeners know that plants inhale carbon dioxide through their leaves as part of the photosynthesis process. However, many don’t realize that humidity affects transpiration rates in plants.

Humidity can also have a negative impact on a plant’s ability to keep its shape. When a plant’s cells lose water, it signals that they aren’t maintaining enough turgor pressure, causing them to wilt and change the shape of their stomata.

In extreme situations, plants can even shrivel and die! Look for brown tips on leaf edges or shriveled buds and flowers.

Relative humidity (RH) is a measure of the amount of water vapor in the air. It is RELATIVE to the temperature of the air, and it’s often higher in cool air than in warm air.

Pests

Whether you enjoy gardening or you’re a novice, learning about the different types of pests that invade your garden plants can help keep them healthy. Some pests are beneficial, while others are harmful.

Among the most common garden pests are aphids, whiteflies and caterpillars. Aphids feed by sucking plant sap and release honeydew, which encourages the growth of sooty mold fungi.

Caterpillars, also called foliar feeding insects, have chewing mouthparts that can damage leaves and buds in a short period of time. Some bore into stems to feed, while other caterpillars eat plant tissue on the leaf surface.

Regardless of the type of insect causing the problem, black tips on leaves are usually an indication of a problem. If you notice any of these signs, make sure to act quickly. Otherwise, it may be too late to save the plant. A trained professional can help you determine the cause of the issue and suggest ways to eliminate it.

Diseases

Plants may turn black tips on leaves as a result of disease, stress, and other factors. This is a good sign that something is wrong and needs to be addressed right away.

Some plant diseases are easily treated with fungicides. These can be sprayed over the entire plant, focusing especially on the affected areas.

Bacterial leaf spots and stem rot, for example, are usually fatal to plants if they are not treated immediately. They can also infect other plants, especially if you share irrigation water with infected plants.

Some bacterial diseases can be difficult to control, especially because they often have rapid emergence and bacterial resistance develops rapidly. Symptoms include leaf spots, wilting, and dieback.

Water

Black tips on leaves outdoor plants can be a sign of water stress. When the roots of a plant absorb more water than they can use, water pressure begins to build in the cells of the leaves.

Eventually, the cells will burst and look like blisters on the leaves. Those areas will then develop tan, brown or white wart-like growths in their place, plus you’ll also notice indentations directly above them on the top sides of the leaves.

This can be a sign that your plant is struggling to absorb enough water and that you need to adjust your watering schedule. In addition, it may be a sign that your soil or substrate is too wet.