Hebe is a genus of flowering shrubs native to New Zealand and South America. They make an excellent low shrub, and are suitable for rock gardens – but sometimes you may encounter hebe leaves turning brown and be left wondering what to do.
If you are dealing with hebe leaves turning brown it is usually a result of watering problems, lack of sunlight or a disease such as leaf spot.
The easiest way to prevent this is to know how to care for your hebe correctly to maintain the leaves, so let’s jump into the basics and some key care points you need to follow to prevent your hebe leaves turning brown.
Hebe has several common varieties. It requires a moderate amount of water and lots of sun. It does well in full sun or partial shade, but too much shade can prevent the plant from blooming.
Some grow from 1 to 3 feet, while others reach 5-6 feet at maturity. Generally, the smaller cultivators are colder tolerant than larger varieties.
Most thrive in zones 7-10. A few varieties require zone 8 to do well. Small cultivators that can be container grown can be grown in more northern zones and brought inside during the winter. Flowers vary from cultivator to cultivator. Some species have purple blooms, while others present pure white flowers.
Overview of Hebe Problems
Hebe is a hardy plant, but there are a few problems that you can encounter with the plant.
The most common issue is overwatering, which can lead to root rot. Lack of sunlight can also cause your Hebes leaves to turn brown. Leaf spot disease is another culprit.
The most common cause of Hebe leaves turning brown is over or under-watering. Both of these can severely impact your Hebe.
Underwatering can spell disaster for plants, including Hebe. It is fairly drought-tolerant, and more likely to be over watered rather than under-watered. However, underwatering can certainly be a problem.
One sign of lack of water is wilting. The plant will begin to wilt and droop. The leaves, particularly on the edges, will turn brown. The Hebe’s growth will slow, and it may not bloom if underwatered. You can also check the soil around the Hebe.
You can differentiate between under and overwatering by the texture of the leaves. Underwatered leaves will fill dry and papery, while overwatered leaves feel soft and pliable. If the soil is very dry, this is another indication your Hebe may be underwatered.
Overwatering also causes problems for the Hebe. Overwatering is a problem itself. It can prevent the plant from bringing in the water and nutrients the plant needs. Essentially, the roots can’t function properly in waterlogged soil. This can cause wilting, brown leaves, and stunted growth.
If you think your Hebe is overwatered, feel the soil. If it’s wet a few inches beneath the surface, overwatering is the culprit.
Waterlogged soil is problematic by itself. However, when it leads to root rot, the problem gets much worse. Wet soil conditions allow the fungus to thrive. This fungus will then attack the roots of the plant. Over time, root rot causes the roots to become brown and mushy.
These damaged roots cannot function properly. The plant isn’t able to take in the nutrients and water it needs, because it is losing viable roots. The leaves will become brown. Eventually, the stems may turn brown as well. Growth will become stunted. The plant can die if root rot isn’t treated early.
How to Water Hebe
Hebes generally need water about once a week. During the hot, dry summer, you may need to water more often. If the Hebe begins to wilt, or the leaves turn brown, check the soil. If the soil is dry, you need to water it more often to keep it in optimal health.
Managing and Preventing Root Rot
The best treatment for root rot is prevention. Avoid keeping the soil wet. You’ll also need to be sure that the soil is well-draining. If the soil is dense or contains a lot of clay, add some sand, perlite, or mulch to provide drainage.
If root rot occurs, you have a few options. If it is container-grown, remove it from the container. Rinse the roots well. Remove any mushy roots, cutting an inch above the mushy area.
Use fresh soil, and preferably a fresh container. If you choose to use the same container, bleach it thoroughly to kill any fungus. Be sure the container has drainage holes to prevent waterlogged soil.
Before replanting, dip the roots in a fungicide to kill any remaining fungus on the roots. You may also want to prune the plant, removing up to 1/3 of its leaves. This is important if the Hebe lost a significant number of roots because it is difficult for it to support all its growth.
If your plants are growing in the ground, treatment options are more limited. You can try applying a fungicide. If caught early, this may save your plants. If it continues to worsen, you’ll need to remove the plant to prevent root rot from spreading.
If it’s badly damaged, you’ll need to dispose of the plant. If it has a chance of survival, consider following the directions for container-grown plants, and replant in a container. Do not plant any other plants in the area until the soil has been solarized or a fungicide is applied. The soil will harbor root rot fungi.
Lack of Sunlight
Hebe loves sunlight. It will thrive in full sun or partial shade. However, if they don’t get enough sun, the leaves will turn brown. The plant isn’t getting enough sunlight to perform proper photosynthesis. Essentially, your Hebe is starving.
Treating Lack of Sunlight
If your Hebe needs more sun, there are a few ways to provide it. If there are trees or other plants giving your Hebe too much shade, consider pruning them. Your other option is to move your Hebe to a sunnier area.
Septoria Leaf Spot
Septoria leaf spot, also known as leaf spot disease, causes brown spots on the leaves. It usually isn’t very harmful, but it can reduce the vigor of your Hebe. It also affects its appearance. It typically occurs in October-February, but it can occur as early as June. Septoria leaf spot is caused by a fungus.
Treating Septoria Leaf Spot
If it’s caught early, you may be able to remove the diseased leaves. Dispose of them carefully, because the fungal spores can travel to other leaves. You can do this by burning.
If further action is needed, you can use a fungicide. This will prevent new leaves from becoming infected. Effective fungicides include chlorothalonil, maneb, mancozeb, or copper-based fungicide.
To prevent or slow the spread of leaf spot, ensure air circulation between the plants. Avoid overhead watering, because this can increase the chances of leaf spot disease.
Final Thoughts on Hebe Leaves Turning Brown
Hebe leaves can turn brown for a number of reasons. The most common issue is overwatering. Underwatering, lack of sunlight, and leaf spot are also potential causes.
Well draining soil, proper watering, and adequate sunlight are good starting points for caring for your Hebe.