I’ve been doing a permaculture plan for a client of mine, and they asked if I could look into why some of their blackberry bushes are dying. To help them out, I put together this guide.
Blackberry plants die from improper watering, nutrients, and climate as well as transplant shock, pests, and diseases. The most common issue is watering, which can be avoided by only watering when the top 2-4 inches of soil gets dry. Additionally, provide 2 inches of compost and at least 4 inches of mulch.
While blackberry bushes die from several common causes, can they be saved, and how can they be treated? Let’s take a closer look.
Can Dying Blackberry Bushes Be Saved?
Dying blackberry bushes can be revived if you find the proper issue and apply a timely solution. However, the hard part is finding out which issue is affecting them.
A good approach is to start with the possible issues based on the symptoms and try solutions starting from the least invasive to the most invasive.
The reason why we want to start with the least invasive solution first is to minimize your blackberry plant’s stress. This will give it the best chance of recovering.
For example, if we’ve narrowed down the possible issues to a lack of water or excess drainage, it’s much easier on the blackberry bush to adjust its watering than it is to dig it up or spray it with chemicals.
By approaching solutions in this way, it makes it much easier for you to treat your blackberry plant, as work your way up from simple solutions to more complex ones.
How to Tell If Your Blackberry Plant Is Dying
| Blackberry Plant Symptom | Issue* |
|---|---|
| Curling or Wilting Leaves | Under-Watered, Heat Stress, Transplant Shock |
| Yellow Leaves | Under/Over-Watered, Transplant Shock, Lack or Excess Nutrients, Pests |
| Brown Leaves | Under-Watered, Heat/Frost Stress, Transplant Shock, Pests |
| Red Leaves | Frost Stress, Lack of Nutrients, Disease |
| Spotted Leaves or Fruit | Pests or Diseases |
| Dropping Leaves | Under/Over-Watered, Heat/Frost Stress, Transplant Shock, Lack or Excess Nutrients, Pests or Diseases |
| Dropping Fruit | Under/Over-Watered, Heat/Frost Stress, Transplant Shock, Lack or Excess Nutrients, Lack of Pollination, Pests or Diseases |
It’s sometimes difficult to tell if your blackberry bush is dying, but generally, if it has any of the above symptoms, it’s likely declining in health.
Keep in mind that these symptoms aren’t normally a cause for concern if they’re affecting less than 10-20% of the plant. For example, it’s fairly normal for 10-20% of your blackberry plant’s leaves to be yellow or brown. The same is true for some flower or fruit drop.
However, if more than 20% of the plant is affected, or you’re seeing other concerning signs such as pest or disease symptoms, then action is likely needed to save the plant.
Keep in mind that blackberry bushes are deciduous plants, so it’s normal for their leaves to turn red and yellow, and drop in the fall and winter. This is a strategy to reduce the plant’s energy expenditure and go into dormancy to survive the winter (much like bears hibernating).
On the other hand, evergreen fruiting plants adapted to the cold differently or are native to more tropical climates (with little to no frost). As a result, evergreen fruits, such as citrus trees, keep their leaves green year-round.
So, don’t stress if your blackberry plant is losing its leaves in the fall or winter!
However, if your blackberry plant is losing its leaves early (in the spring or summer), or has other symptoms, continue reading to see what we can do to help it.
3 Quick Steps To Save a Dying Blackberry Bush
If you’ve already tried finding out which issue your blackberry has, and you’ve gotten stuck, there’s still hope.
Here are 3 steps you can use to save your blackberry plant, for just about any condition.
1. Identify the Possible Issues
The first step in reviving a dying blackberry plant is to identify the possible issues. After all, the process of elimination wouldn’t work if we didn’t know which options we were eliminating!
If you haven’t seen them yet, reference the below sections for the top 7 most common blackberry bush issues.
2. Isolate the Actual Issue
Once you’ve checked the specific symptoms your blackberry has, you can now cross off potential issues from your list.
Try to get it down to 1-3 potential issues that best match the symptoms your blackberry plant is exhibiting. This gives you the best chance to provide the right solution for it (you don’t want to repot the plant if the problem is a watering issue).
3. Test Solutions
Now that you have a narrowed-down list of the potential issues, it’s time to try the solutions one at a time.
Start with the least invasive solution and work your way up to the most invasive. Again, it’s much easier on the plant (and you) to provide less water than to repot or transplant it. Try to save those options for last.
Continue testing the treatments you believe are most likely to fix the issue. Hopefully, one of them sticks.
Worst case scenario, start from step 1 and make a new list of possible issues. There’s a chance you might have missed something or noticed something new the second time around.
Stay persistent! It’s easy to say, “Dumb plant, why don’t you want to live?”, but there’s always a reason why plants act the way they do. Stay the course and see if you can uncover it.
If you have no idea what issue your blackberry plant might have, that’s okay! That’s what I’m here for. To give you a head start, let’s explore the 7 most common reasons blackberry bushes die.
The Top 7 Reasons Why Blackberry Bushes Die
1. Under-Watering
Under-watering is one of the most frequent reasons blackberry plants die and it’s especially common if you get hot and dry summers.
The best way to water blackberry bushes is to only water when the top 2-4 inches of soil is dry. I check this by pushing a finger into the soil, under the plant’s drip line. When watering soak the ground at least 2 feet deep.
The goal when watering is to have soil moisture similar to a wrung-out sponge.
Since over 90% of the plant’s roots are found within the first 2 feet of soil, soaking the soil ensures the majority of the roots get water.
Deep watering like this encourages the plant to grow deeper roots, which provides it with deeper water and better anchorage.
On the other hand, shallow and frequent watering encourages shallow roots and makes drought stress and wind damage more likely.
Apply 2 inches of compost and 4 inches of mulch under the plant’s drip line. Reapply compost every 1-2 months and mulch every 3-6 months. Keep both materials at least 3 inches from the blackberry bushes to avoid mold buildup.
Compost provides essential nutrients and increases the soil’s water retention. Every 1% increase in the soil’s organic matter leads to an additional 20,000 gallons of water held per acre. Compost also feeds the soil life, leading to benefits such as increased nutrients and pest and disease resistance.
Mulch dramatically reduces evaporation, regulates soil temperature, and prevents soil erosion. Since blackberry bushes evolved as understory species in forests, they prefer plenty of mulch in the form of fallen leaves and branches.
As permaculture guru Geoff Lawton says, a forest grows on a fallen forest.
Both compost and mulch also amend soils that drain too quickly. But what happens if the soil has poor drainage?
2. Over-Watering (Poor Drainage)
While both under and over-watering can be prevented by only watering when the soil is dry, if the soil has poor drainage it can become waterlogged and lead to issues such as root rot (more on this later).
You can tell if your blackberry plant’s soil is getting over-watered if the soil is staying sopping wet for 24 hours or longer. If it stays wet for too long, the soil will start smelling like a swamp and the blackberry plant’s leaves turn yellow and drop.
Over-watered soils are most often a result of ground that’s depressed, compacted, or high in clay.
Here are some quick steps to fix poorly draining soil.
- Test
- Amend
- Mulch
Let’s expand on these steps.
Percolation Test
A good way to test your soil’s drainage is by doing a percolation test.
- Dig a 1-foot by 1-foot hole
- Place a yardstick in the hole and fill it with water
- After an hour, measure the water line on the yardstick
The goal for proper drainage is about 2 inches per hour. However, this is a guideline and not a rule, so don’t worry if yours is way off. This is just a way to see if your soil has poor or fast drainage.
I recommend digging at least 3 different holes across your property as some areas might have much better drainage than others.
Amend Poorly Draining Soil
Once you determine your soil’s drainage, it’s time to amend it.
Interestingly, the solution for both poor drainage and fast drainage is the same—compost.
Compost not only breaks up the clumps of ground in poorly-draining soil, but its organic matter retains water in fast-draining soils.
As mentioned above, I recommend providing your blackberry plants with 2 inches of compost every 1-2 months. Over time, the compost will work its way into the soil and amend it.
If you can’t wait for the compost to do its job on the soil, you can also move your blackberry plant to an area with better drainage such as a raised bed or mound of soil.
On the other hand, potted blackberry plants that have poor drainage should be amended by repotting them with fresh potting soil.
Provide Mulch
Once your blackberry plant has well-draining soil, provide 4 inches of mulch to give it a big boost of water retention and protection from the elements.
Some good mulches for blackberry bushes are leaves, straw, grass clippings, and pine needles.
Recommended: 10 Expert Tips for Watering Fruit Trees
Let’s move on from watering to other reasons why blackberry bushes die.
3. Transplant Shock
If your blackberry plant was recently planted or repotted, and it’s starting to die, it’s probably due to transplant shock. Transplant shock occurs when the plant is exposed to a new environment and has to establish a new root system.
Avoid transplanting unless necessary as it can take up to 1 year for recovery.
To help avoid transplant shock, I like to plant with the following steps in mind:
- Have the new ground (or pot) prepared
- Remove as much of the plant’s current topsoil as possible, without damaging the shallow roots
- Grab the base of the plant’s stem and wiggle lightly
- Using your other hand, scoop up and support the rootball
- Lightly place the plant in the new ground (or pot) and fill it in
- Make sure the soil is at the same level on the stem as before
- Apply 2 inches of compost and 4 inches of mulch to the top of the soil
- Water generously and add more soil as needed
4. Improper Nutrients
Excess Nutrients
When blackberry plants get too many nutrients, their roots are chemically burned, causing the plant stresses the plant and causes a decline in health. Excess nutrients are often caused by fast-release chemical fertilizers as compost isn’t potent enough.
If you believe you’ve over-fertilized your blackberry plant, I suggest removing as much of the fertilizer as possible via leaching.
To leach, heavily water your blackberry plant’s soil to dilute the existing fertilizer and allow it to flow deeper into the soil (and out of reach of the plant’s roots). You may have to do this at least a few times.
Avoid leaching if your soil has poor drainage as the soil can become waterlogged.
In this case, either apply generous amounts of compost and garden soil to dilute the chemical nutrients, or repot the plant with fresh potting soil (for potted blackberry plants).
A Lack of Nutrients
| Nutrient Deficiency | Leaf Symptom |
|---|---|
| Nitrogen | Entire leaf is pale or yellow |
| Iron | Dark green veins, rest of the leaf is yellowing |
| Zinc | Yellow blotches |
| Manganese | Broadly pale leaves, foliage color looks mottled or smeared |
If you haven’t fed your blackberry plant in the past several months, there’s a good chance it may be dying from a lack of nutrients.
Symptoms of a lack of nutrients depend on the deficiency.
For example, blackberry bushes commonly get a nitrogen deficiency and get lightly colored or yellow leaves.
Let’s take a look at the ideal way to prevent a lack of nutrients for your blackberry plants.
The Best Way To Fertilize Blackberry Bushes
If you decide to use a chemical fertilizer, opt for one with a balanced NPK (nitrogen, phosphorus, and potassium), such as a 10-10-10.
Each brand has different percentages, so follow the instructions on the label for the best results.
If you’d like to see more about the fertilizers I recommend, check out my recommended fertilizer page.
Alternatively, you can use compost.
I recommend applying 2 inches of compost every 1-2 months under the plant’s drip line followed by 4 inches of mulch.
Keep in mind that while nutrients are essential, they aren’t everything.
Imbalanced Soil pH
Blackberry bushes prefer a soil pH of 5.5-6.5.
The reason blackberries (and most plants) prefer a slightly acidic soil pH is that it dissolves the nutrient solids in the soil, making them more accessible to the plant’s finer roots.
Fourteen of the seventeen essential plant nutrients are obtained from the soil. Before a nutrient can be used by plants it must be dissolved in the soil solution. Most minerals and nutrients are more soluble or available in acid soils than in neutral or slightly alkaline soils.
Donald Bickelhaupt, Instructional Support Specialist, Department of Forest and Natural Resources Management
When blackberry bushes have an imbalanced soil pH, they develop issues such as discolored and dropping leaves. Additionally, their flowers and fruit drop early and the plant is more likely to develop other growth issues.
Two good ways to test your soil’s pH are with pH strips or a meter. I prefer using a pH meter since they’re affordable and easy to use. To see which pH I recommend, check out my recommended tools page.
If you find your blackberry plant’s soil is too alkaline (above 6.5), provide acidic amendments such as peat moss, sand, and coffee grounds.
On the other hand, if your soil is too acidic (under 5.5), provide alkaline amendments such as charcoal, wood ash, and lime.
5. Heat or Frost Stress
Blackberry bushes are natively from temperature climates, so they usually prefer cooler environments but a few varieties can grow in warmer areas. Ideally, grow blackberries in USDA hardiness zones 4-10.
Climates that are too cold (below zone 4) or those that are hot and dry quickly pose a problem for blackberry bushes.
Keep blackberry bushes in a cool and mild climate if possible. If the sun is too hot, and the tips of the leaves are curling and browning, provide shade or move potted blackberries indoors. When bringing them indoors, take care to avoid the hot and dry air from the central heat.
Hot Weather
In hot and dry areas such as California, Arizona, Nevada, and parts of Texas, blackberry bushes lose moisture from their leaves and soil quickly. Normally, blackberries do best in temperatures under 90ºF. Any hotter and they start to decline and die.
Much like humans, plants cool themselves by exhaling moisture (called transpiration). Plants also keep themselves cool by sending moisture from their roots to their leaves.
This becomes a problem when the climate is too hot and dry. Essentially, the transpiration and root moisture can’t keep up and cool the plant and its leaves.
As a result, the blackberry bush’s leaves dry, curl, brown, and drop if it’s bad enough.
So, the hotter and drier the weather, the more energy the plant uses to transpire and survive, and the less energy it has to use to establish its root system and grow. This drain of resources can quickly stunt or kill the plant.
The best practices to help your blackberry plant survive hot and dry weather are to provide it with sufficient water, compost, and mulch. Additionally, give it partial shade from the west (as the afternoon sun is the hottest).
If you’d like more information about the best drought-tolerant fruiting plants, check out my other post: 30 Best Drought-Tolerant Fruit and Nut Trees (Ranked).
Cold Weather
If temperatures fall below -20ºF to -30ºF (the standard zone 4 minimum temperature), blackberry bushes will likely start to die.
For outdoor blackberry bushes, you can insulate the plant and its roots by giving it 4-12 inches of mulch.
You can also use windbreaks such as walls or other plants to reduce the effects of windchill. Greenhouses or high tunnels will also work.
I would suggest not moving potted blackberry plants indoors during the winter as they typically require 800+ chill hours to fruit properly in the spring. Since indoor temperatures rarely get this low, it’s normally not a good idea.
Another issue with moving a blackberry plant indoors is that the central heat indoors can dry out the plant quickly.
I found out about the effects of central heat the hard way.
For example, we had a surprise snowstorm last year here in Austin, Texas, and I moved my potted Meyer lemon tree inside. However, it quickly started losing its leaves. After moving it into a cooler room, it quickly started growing new leaves (see the photo below).
When it comes to sheltering your potted blackberry plant during temperatures below -30ºF, move it to a basement or another cool, sheltered location. Try to keep the temperature 45ºF or below to maintain the plant’s chill hours in the winter.
6. Pests
- Aphids – Aphids are small, dot-like bugs that suck the sap from underneath the blackberry plant’s leaves. Treat aphids by spraying water, neem oil, or releasing ladybugs (a natural predator). For example, spraying them with a jet of water worked for my potted Kaffir lime tree.
- Spider Mites – Similar to aphids, mites suck the sap from leaves and can be treated in the same ways. While spider mites are a similar size to aphids, you can tell the difference as they resemble small spiders (they’re part of the spider family).
- Japanese Beetles – Japanese beetles feed on berry leaves and sometimes the fruits. You’ll likely notice them visually or see evidence of holes in the leaves. You can remove and deter them by treating the plant with soap and water or neem oil. Also, you can physically remove the beetles from the leaves (bonus points if you feed them to your chickens!)
- Leafrollers – Leafrollers are small caterpillars that feed on berry leaves, flowers, and green fruit. They use their silk to curl the leaves and hide in them. Treat leafrollers by using pheromone traps and by encouraging natural predators such as beneficial wasps spiders. Sprays are not recommended when treating leafrollers.
7. Diseases
- Root Rot – Root rot is a soil fungus that causes leaves, blossoms, and fruit to droop, yellow, brown, and drop. It typically occurs in waterlogged soil and those with poor drainage. No chemical control is available to treat root rot. However, repotting my potted Kaffir lime tree with fresh potting soil cured it of root rot.
- Verticillium Wilt – Verticillium wilt is a fungal disease in soil that causes leaves to yellow and brown, and can lead to the blackberry plant dying. Already weakened plants from drought, over-watering, and other stressors are more likely to become affected.
- Cane Blight – Cane blight is a fungal disease that affects berry plants, causing wilting and browning leaves, killing part or all of the blackberry plant. This disease usually starts from a wound on the plant. Treat by promoting airflow and sunlight, and pruning infected canes. Sprays are rarely necessary.
- Fire Blight – Fire blight is a common bacterial disease that appears as scorched leaves (hence the name). It affects the rose family (apples, pears, berries, and more). Treat fire blight by pruning and some natural sprays. Some chemical sprays may be effective.
- Rust – A fungal disease that turns blackberry leaves a splotchy red-brown. Treat by pruning and using organic sprays.
A Note on Pesticides, Fungicides, and Herbicides
We recently had an issue with caterpillars eating our basil plants and we were about fed up. Every time we’d plant basil, the caterpillars ate it.
Fortunately, we found an organic spray at our local nursery that’s made from fermented rum. The day after spraying, we’d find dead caterpillars on the soil.
If you’d like to find out more about this organic spray, you can find it here on Amazon.
So, what’s my point here?
Even though chemical sprays and fertilizers are an easy way out, like all easy and convenient things, there are usually long-term costs. Namely to the plants, soil, and surrounding beneficial life.
Before using conventional sprays, weigh the pros and cons and consider trying organic or permaculture-based treatments first.
To give you a head start, Stefan Sobkowiak – The Permaculture Orchard has a great video on a safe, homemade, and most importantly—effective fungicide (hint: the secret ingredient is whey).
Also, check out how Mark Shepard uses a method called STUN (Sheer-Total-Utter-Neglect) to help his berry plants, fruit trees, and nut trees THRIVE.
