It can be scary to see brown leaves on your raspberry plants, but don’t worry—the problem is usually easy to find and fix. Raspberry leaves can turn brown for a number of reasons, such as not getting enough water, problems with the weather, not getting enough nutrients, or pests or diseases. Once you know what might be wrong, you can take steps to make your raspberry plants healthy and productive again.
Watering Issues
One of the most common reasons for raspberry leaves browning is underwatering. Raspberries have relatively shallow root systems and need about 1-2 inches of water per week. If rainfall is lacking drought stress can quickly set in. This causes the leaves to shrivel, dry out, and turn brown along the edges or centers. The damage often starts with older leaves and spreads from there.
Overwatering can also lead to brown leaves on raspberries. While established plants are quite drought-tolerant, they do not appreciate soggy soil. Excess moisture causes stress that leads to yellowing, then browning of the leaves. Roots may rot in very wet conditions.
To prevent watering issues:
- Check soil moisture before watering and only water when the top few inches are dry
- Use drip irrigation or soaker hoses to target water to plant roots
- Improve drainage if the soil stays soggy after rain
- Apply mulch to regulate soil moisture and temperature
Climate Stress
Hot dry weather coupled with intense sun can scorch raspberry leaves especially along the margins. This sunscald damage appears as browned, dry areas on the leaves. It often affects younger or newly transplanted plants that aren’t hardened off to full sun exposure.
On the other end of the spectrum, exposure to harsh, drying winter winds or rapid temperature fluctuations can injure raspberry canes. Damaged leaves then emerge shriveled or browned in spring.
To prevent climate damage:
- Acclimate young plants slowly to direct sun
- Protect canes from winter winds using row covers or plant debris
- Choose disease-resistant varieties suitable for your climate zone
- Provide afternoon shade if possible during hot spells
Nutrient Deficiencies
Lack of important nutrients like nitrogen, potassium, magnesium, and iron leads to yellowing and browning raspberry leaves. This usually starts on older leaves. Without proper nutrients, the plants cannot produce enough chlorophyll, causing the foliage to brown from the edges inward.
To prevent nutrient issues:
- Test soil and apply balanced fertilizer as needed
- Work compost into beds before planting
- Mulch around plants to provide nutrients over time
- Watch for signs of specific deficiencies like overall yellowing or yellowing between veins
Pests
Tiny pests that suck plant sap, like aphids, spider mites, and leafhoppers can cause raspberry leaves to mottle, stipple, or turn brown. Heavy infestations can lead to curled, shriveled leaves as well. Look on the undersides of leaves for evidence of these pests.
To control pests:
- Blast away aphids with a strong jet of water
- Apply horticultural oils or insecticidal soap for mite infestations
- Attract beneficial insects like ladybugs to naturally control pests
- Remove any severely damaged leaves to prevent pest spread
Diseases
Raspberries can get fungal diseases like anthracnose, spur blight, and cane blight, which first turn the leaves spots and brown and then kill the canes. These diseases like it when it’s wet, and they usually get in through cuts or wounds.
Leaves that turn brown are also caused by bacterial diseases like crown gall and fire blight. But bacterial diseases need a way in, like an insect bite or a pruning wound.
To prevent disease issues:
- Promote airflow through proper spacing, pruning, and weed control
- Disinfect pruning tools between plants
- Scout for early symptoms of disease
- Remove and destroy any infected plant material
- Apply appropriate organic fungicides preventatively
When to Worry About Brown Leaves
Some brown raspberry leaves are normal and nothing to worry about. Floricanes (second-year canes that bear fruit) will turn brown and woody after harvest. As long as new primocanes are growing vigorously, this browning is not an issue. It’s also common to see marginal leaf burn due to herbicide or fertilizer exposure, but the plants will outgrow this minimal damage over time.
However, if brown leaves are widespread, spreading, or happening at the same time as slow growth, it probably means there is a bigger problem at play. Find the cause and fix it. That’s the best thing you can do. If you take good care of your raspberry plants, they can grow back from brown leaves and keep making lots of berries for years to come.
Understanding Raspberry Plant Problems
One of the first things you need to know is the difference between a primocane and a floricane. A primocane is a leafy stalk formed during its first year on a raspberry plant. It may produce buds but doesn’t typically produce fruit. You need to let the primocanes grow and then let them overwinter so that they can flower and bear fruit the next year. During the second year of this cane’s life, it is called a floricane. Floricanes produce flowers and fruit. They typically die or become non-productive after that. You should cut floricanes down to ground level after you harvest your berries. Leaving floricanes uncut can lead to unnecessary raspberry plant problems.
3 Raspberry Mistakes To Avoid – Garden Quickie Episode 111
FAQ
Why are my raspberry leaves curling and turning brown?
Raspberry leaves curling and turning brown can be caused by several factors, including pests, diseases, nutrient deficiencies, or environmental issues.
What do overwatered raspberries look like?
Too much moisture can also cause yellow raspberry leaves. Excessive over-watering or prolonged wet weather can lead to the roots sitting in water, reducing root and leaf transpiration. This, in turn, means the plants are unable to absorb any iron and other nutrients from the soil and transport them to the foliage.
How often should you water a raspberry bush?
Raspberry bushes generally need about 1 to 1. 5 inches of water per week, especially during the growing season and especially from bloom until harvest.
Do coffee grounds help raspberry plants?
Yes, coffee grounds can be beneficial for raspberry plants, especially when used in moderation and at the right time. Nitrogen is an important nutrient for plant growth, and coffee grounds are a good source of it. They can also help the soil drain and breathe better.