Bay laurel is a tough, slow-growing evergreen, so trouble usually shows up first in the leaves. Yellowing, stickiness, spots and browned edges are the signs gardeners notice most. Most of them trace back to how the tree is grown (its roots, its soil, its pot and its exposure) more than to disease. Fixing the cause usually brings back healthy new growth, even though leaves that are already damaged won’t recover. Only laurel wilt, found in the southeastern US, is usually fatal.
Yellow Leaves From Wet Roots
Bay needs soil that drains well. If its roots sit waterlogged, they easily develop root rot, which turns the leaves yellow and makes the plant droop.1Gardening Know How. Bay Laurel Has Yellow Leaves: Why Is My Bay Laurel Turning Yellow Clay or constantly wet soil raises that risk.2Blossomdale. Bay Laurel: The Essential Guide to Growing and Caring for Laurus nobilis Trees Bay can cope with heavy clay on a slope that dries out, but not with soil that stays waterlogged through winter.3Ashridge Blog. 6 Common Bay Tree Problems & Solutions
In soggy soil the air pockets fill up, so the roots effectively suffocate. Damaged roots can no longer take up water, which means the leaves can wilt even though the soil is wet. A drooping bay in wet soil needs less water, not more.
To check, push a finger a few inches into the soil. If it’s soggy days after watering, drainage is the problem. With a potted bay, tip it out and look at the roots: healthy ones are firm and pale, while rotten ones are brown, soft and smell sour. Also make sure the drainage holes aren’t blocked and the pot isn’t standing in a saucer of water.
The extra water is often accidental, coming from lawn sprinklers or runoff from a road or path.4Ashridge Blog. 6 Common Bay Tree Problems & Solutions A low spot in the garden can also simply be too wet for bay.5Ashridge Blog. 6 Common Bay Tree Problems & Solutions Mixing compost or grit into heavy soil improves drainage and root health.6Blossomdale. Bay Laurel: The Essential Guide to Growing and Caring for Laurus nobilis Trees
To rescue a waterlogged tree, stop watering until the top layer of soil dries. Repot a potted bay into gritty, free-draining mix and trim away any mushy roots. A garden bay can move to a higher, drier spot if the ground stays soaked in winter.
Sticky Leaves and Black Coating From Scale and Other Sap Suckers
Scale insects, aphids and mites suck the plant’s juices.7Melinda Myers. Bay Leaf Plant Has Sticky Leaves with Black Spots As they feed, they give off a sweet, sticky fluid.8Extension. How can I get rid of brown soft scale on my bay laurel? A black fungus called sooty mold then grows on it, making the leaves look dirty.9Extension. How can I get rid of brown soft scale on my bay laurel? The mold doesn’t infect the leaf itself. It harms the plant by coating the leaves and blocking light.10Smart Gardener. Bay Laurel: Bay Laurel Outdoors, the sticky residue draws flies, wasps and ants; indoors it mostly draws ants.11University of Maryland Extension. Scale Insects on Indoor Plants
The pests themselves are easy to miss. Adult scale females stay in place under a hard or waxy shell, so they are often mistaken for part of the plant. The first clue is usually the sticky residue or black coating rather than the insects. Look on the undersides of leaves and along stems for small brown bumps that don’t move. They scrape off with a fingernail, unlike natural markings on the leaf. Ants walking up the trunk suggest there is sticky residue above. Aphids are softer and move about, and they cluster on tender new shoots, so check the growing tips. Heavy scale infestations reduce vigor and stunt growth, and long-running ones can cause wilting, early leaf drop and the death of shoots.12Extension. How can I get rid of brown soft scale on my bay laurel?13University of Maryland Extension. Scale Insects on Indoor Plants
Gentle treatments work well. Insecticidal soap kills soft-bodied insects on contact, and neem oil disrupts pests’ life cycles.14Tree2mydoor. How to Treat Bay Tree Pests? | Mytree Information Hub Sprays only work if they actually touch the pests, so coat the leaf undersides and stems, not just the tops. Soaps and oils can scorch leaves in strong sun or heat, so spray in the cool of the morning or evening. Soft young crawlers are the vulnerable stage of scale, and hard-shelled adults resist sprays, so expect to treat repeatedly over several weeks.
On a small potted tree with only a few scale, hand wiping is enough. A damp cloth or soft brush leaves no residue on leaves you cook with. Wash the black coating off with warm soapy water; once the pests are gone, it fades. Rinse leaves well before harvesting, and follow the product label on how long to wait after spraying. Check again every week or two, because young scale hatch in waves.
Spots, Blisters and Dead Patches on Leaves
Leaf spot is a fungal disease that shows as gray or brown dead spots.15Homes and Gardens. Bay tree problems – how to spot and remedy these 5 common issues Remove affected leaves and rake up fallen ones.16Homes and Gardens. Bay tree problems – how to spot and remedy these 5 common issues Water early so the leaves are dry by mid-morning, which discourages spores.17Gardening Know How. Sweet Bay Leaf Spots: Care Of Bay Tree Leaf Problems A balanced fertilizer in early spring encourages clean new growth.18Homes and Gardens. Bay tree problems – how to spot and remedy these 5 common issues Spraying is not usually needed; if you do use a sulfur spray, start at bud break in spring and repeat every 12 to 14 days.19Gardening Know How. Sweet Bay Leaf Spots: Care Of Bay Tree Leaf Problems
Edema is different. It appears as small raised blisters or corky brown patches, mostly on the leaf undersides.20Botanicaly. Edema on plant leaves: bumps, blisters and corky spots The roots take up water faster than the leaves can release it, so leaf cells swell and burst.21leafscan.app. Leaf Edema: Why Your Plant Is Growing Tiny Blisters (and How to Fix It) It’s most likely when soil is warm and moist while the air is humid, cool, dim or still.22Wisconsin Horticulture. Edema To fix it, water less during cool, cloudy spells and improve airflow and light around indoor bays. Damaged leaves won’t heal, but new leaves will come in clear.
Fungal spots are flat, gray or brown, and spread. They can appear on the upper surface as well as the underside and often grow larger over time, while blisters begin mainly underneath.
False spider mites are too small to see without magnification, yet they cause unexpectedly large dead patches.23Richters Herbs. Richters Herbs They are one possible cause when new dead patches appear with no visible insects; a magnifying glass can confirm them. Wiping the leaves daily for a week with a pyrethrum soap solution can clear them.24Richters Herbs. Richters Herbs
Yellowing From Hungry or Alkaline Soil
Yellowing between veins that stay green usually means the plant can’t get enough iron, often because the soil is too alkaline or the roots are damaged.25Gardening Know How. Bay Laurel Has Yellow Leaves: Why Is My Bay Laurel Turning Yellow Even yellowing that starts on the older, lower leaves and moves upward points to too little nitrogen.26Gardening Know How. Bay Laurel Has Yellow Leaves: Why Is My Bay Laurel Turning Yellow Bay does best at a soil pH of about 6.0 to 7.5, slightly acidic to neutral.27Blossomdale. Bay Laurel: The Essential Guide to Growing and Caring for Laurus nobilis Trees
Where the yellowing starts is the clue. Nitrogen can move from old leaves to new growth, so the oldest, lowest leaves fade first and the newest stay greenest. Iron doesn’t move around the plant that way, so the yellowing between green veins appears on the youngest leaves at the tips first.
Waterlogging, by contrast, yellows leaves more generally and comes with soggy soil and drooping. Check soil moisture before reaching for fertilizer, since feeding a rotting root system only adds to its problems.
To lower the pH, use sulfur or peat moss.28Gardening Know How. Bay Laurel Has Yellow Leaves: Why Is My Bay Laurel Turning Yellow Correct a nitrogen shortage with compost or a nitrogen-rich fertilizer.29Gardening Know How. Bay Laurel Has Yellow Leaves: Why Is My Bay Laurel Turning Yellow Potted bays run short of nutrients most often, because they can’t reach the soil’s supply.30Ashridge Blog. 6 Common Bay Tree Problems & Solutions
Inexpensive pH kits from garden centers give a reading in minutes, and a pH above 7.5 makes alkaline soil a likely cause of yellowing between green veins. For a pot, feeding through the growing season is usually simpler than testing. Using rainwater instead of hard tap water helps keep potting mix from turning alkaline.
Drooping in a Pot That’s Too Small
Soil that dries out almost as soon as you water is a sign the bay needs repotting.31Meadowlark Journal. Repotting a Bay Tree: 6 Easy Steps Limp leaves or regular drooping suggest the container is too small.32Meadowlark Journal. Repotting a Bay Tree: 6 Easy Steps Constantly dry soil can stunt new growth.33Meadowlark Journal. Repotting a Bay Tree: 6 Easy Steps
Roots circling the inside of the pot or poking out of the drainage holes confirm the tree has outgrown its container. Slide the plant out and check: if there are more roots than soil, it’s root-bound.
Repot in spring, moving up just one pot size to a container with drainage holes. Use a gritty, free-draining mix and loosen circling roots gently. Water well afterward, then let the top of the mix dry between waterings.
Brown Leaves From Cold and Wind
Bay survives down to about -5°C (23°F), but frost and cold winter winds can damage the foliage.34RHS Advice. Bay Tree Care and Uses Below -5°C, wrap the plant or move it into a garage or a cool room no warmer than 10°C (50°F).35RHS Advice. Bay Tree Care and Uses The best outdoor spot is a sheltered corner against the wall of a heated house, out of strong wind.36Top Topiary. Bay Care Guide – Caring for Laurus nobilis Topiary Potted bays get cold faster than plants in the ground, so move them earlier.
After a freeze or cold wind, leaves browned along the edges or tips, or crisp and brown all over, are the usual signs. It may appear days or weeks after the cold event, so don’t judge straight away.
Wind matters as much as temperature. Bay keeps its leaves in winter, and cold wind pulls moisture out of them faster than cold or frozen roots can replace it. Brown, dry leaves in late winter can come from this drying out, even when the temperature never fell far.
Remove winter-damaged or broken branches in late spring.37Gardening Know How. How To Prune A Bay Tree – Tips For Cutting Back Bay Trees Cut back to the nearest healthy leaves or new buds using clean, sharp tools.38Gardener’s Path. When and How / When and How to Prune Bay Laurel Overgrown or badly damaged bays can handle a hard cut, removing a third of the plant in the first year and another third the next.39Gardener’s Path. When and How / When and How to Prune Bay Laurel
Brown leaves don’t always mean the branch is dead. Scratch the bark: green underneath means the stem is alive.
Laurel Wilt and Curled Leaves From Bay Sucker
Laurel wilt has killed bay laurels in Florida. The signs are wilted leaves, stained wood under the bark, and small beetle holes.40PubMed. First Report of Laurel Wilt Caused by Raffaelea lauricola on Bay Laurel (Laurus nobilis) in the United States A beetle carries a fungus into the wood, and the tree’s own defensive reaction blocks its water flow, so infected trees wilt and die.41American Journal of Plant Sciences. An Uncertain Future for American Lauraceae: A Lethal Threat from Redbay Ambrosia Beetle and Laurel Wilt Disease (A Review) Beetle holes can leave sawdust in thin sticks that look like toothpicks.42PubMed. First Report of Laurel Wilt Caused by Raffaelea lauricola on Bay Laurel (Laurus nobilis) in the United States
The disease moves fast. The whole tree or large parts of it wilt and turn brown within weeks, whereas cold or root problems tend to show in patches or over a longer time. Dead leaves tend to hang on the branches instead of dropping. Changing watering or feeding makes no difference.
Infected wood or firewood can carry the beetle and fungus to new areas, which is why moving it is discouraged. Other trees in the laurel family, such as avocado and sassafras, can also be affected, so a neighbor’s sick tree is a warning sign.
If you suspect laurel wilt, contact your local extension office to confirm it, and don’t move firewood from an affected tree. Pruning can’t cure it.
The bay sucker is a small insect that causes young leaves to curl and grow misshapen.43EPPO Bulletin. First report of the bay sucker <i>Trioza alacris</i> Flor (Triozidae: Hemiptera) in Tunisia Pick off and dispose of the curled leaves.
Is It Really Bay Laurel
Leaves of Laurus nobilis are not toxic.44Gardening Know How. Are Some Bay Leaves Toxic – Learn Which Bay Trees Are Edible Mountain laurel, though, is poisonous in all its parts.45Gardening Know How. Are Some Bay Leaves Toxic – Learn Which Bay Trees Are Edible California laurel is safe to eat but much stronger tasting.46Gardening Know How. Are Some Bay Leaves Toxic – Learn Which Bay Trees Are Edible
Many unrelated shrubs are called laurel, and common names don’t tell you whether a plant is safe. Cherry laurel is a common hedge plant that is also not safe to eat, and its leaves can look similar to bay. Only Laurus nobilis, the true bay, is the cooking leaf.
Check the plant tag for Laurus nobilis. True bay leaves smell aromatic when crushed. If you’re unsure, ask a nursery before cooking with the leaves.