Blackberry fruit is produced by many species present in the Rubus genus that belongs to the Rosaceae family. Just like raspberries, blackberries are also extremely easy to grow, and they grow in abundance.
However, fruits can oftentimes face issues while growing, and the same goes for blackberries.
One such issue is the white spots on your blackberries.
In this article, you will learn what it means when your blackberries have white spots and you’ll also come to know what you can do about it.
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Why Are There White Spots on My Blackberries?
One of the main reasons why your blackberries have developed white spots is due to something known as white drupelet syndrome. This condition occurs when an issue related to sunlight, temperature, and wind causes harm to blackberry fruits. However, white spots can also occur due to the presence of pests such as spider mites and stinkbugs.
White Spots on Blackberries Caused by White Drupelet Syndrome
Blackberries have what is known as drupelets. Drupelets are small individual balls on your blackberries that surround the seed.
Sometimes you will find that blackberry has white color on its drupelets. This white discoloration is known as white drupelet syndrome/disorder.
This is a common issue found in both, raspberries and blackberries, but it does not mean the fruit is unsafe to eat. However, markets do not sell blackberries suffering from white drupelet syndrome because it is considered unsightly.
White drupelet syndrome can be caused due to several issues related to sunlight, wind, and temperature.
Blackberries do best under direct sunlight. They need at least six to eight hours of sunlight to grow an abundance of fruit.
However, sunlight can also cause the plant to tan or develop white spots. It is important to make sure that all parts of your blackberry plant are receiving the same amount of sunlight.
Cold drying winds between 20 to 24 degrees Fahrenheit (-7 to -4 degrees Celsius) can cause damage to the canes. This, in return, causes your blackberries to develop white spots when the harvest season arrives.
Blackberries can survive in temperatures as low as -10 degrees Fahrenheit (-23 degrees Celsius), but this can varies depending on the cultivar.
Blackberries that are frost tender can only survive temperatures as low as 0 to 10 degrees Fahrenheit (-17 to -12 degrees Celsius).
Also, high temperatures can cause your blackberries to develop white spots. Thus, it is better to keep your blackberry plants in moderate temperatures.
White Spots on Blackberries Caused by Pests
White spots on blackberries can also be caused due to the presence of pests. Feeding insects such as red spider mites or stick bugs are a common occurrence on blackberries.
The damage can be seen as a tan or the drupelets turning white in irregular patterns.
Red spider mites are almost microscopic and hard to spot. Often times you will need to inspect the leaves of the plant to get rid of red spider mites.
The best place to spot them is by having a look at the bottom side of the leaves. If you see any dusty appearance on the bottom of the leaves, it is a clear sign of a spider mites infestation.
Stink bugs are easier to spot as compared to spider mites. This is because they are often seen as black flecks on leaves.
Stink bugs are also much larger in size and do not go unnoticed once several of them have surrounded your plant.
Solutions for White Drupelet Syndrome
Change Your Blackberries Position
You can reduce the problem related to sunlight by planting your blackberries so that they run from north to south.
This is better than letting your plant run east to west since the plant gets sufficient sunlight from all sides when running from north to south.
You should also plant your blackberries in an area where slight shelter is present. This is because, during intense heat and dry winds, your plant should not go through any form of stress.
Provide Proper Shade
The best way to protect your blackberries from drying is by providing them with some shade. The shade can be installed, but it should not cover the plant completely.
Covering the plant will cause fewer bees to reach the plant, and your blackberry plant will not be able to pollinate.
Provide Proper Temperature Levels
It is always better to plant your blackberry plant in a colder area compared to a hotter one. The majority of blackberry plants thrive in cold areas, which is why you should regulate the temperatures surrounding the plant
You can also try planting a blackberry plant that is more tolerant to high temperatures.
Ways to Protect Your Blackberries from Pests
Spider mites are most active in hot temperatures, which is why they are likely to attack plants during summer or spring. The best way to control their infestation is by using natural predators.
You can use lacewings or ladybugs to get rid of spider mites. You can easily find these natural predators in any gardening center.
You can also use pesticides and insecticidal soaps against spider mites. Organic solutions such as neem oil are also recommended.
Suppose you use natural predators and also wish to use other methods against red spider mites. You need to make sure you do not spray pesticides as they can kill natural predators as well.
Make sure you provide some form of protection against dry winds since spider mites like dry environments.
Stink bugs love to attack plants once winter comes to an end and temperatures start to rise. To keep stink bugs away, you should first remove weeds or overgrowth around your blackberry plant.
Stinkbugs like to use debris as a cover. If you are growing blackberries indoors, you should keep all doors and windows shut; this will prevent them from entering your home.
You can also use kaolin clay solution as another bug control method. This prevents stink bugs from laying eggs and feeding off of your plant.
Frequently Asked Questions about White Spots on Blackberry Plants
Can I eat Blackberries that have white spots on them?
Blackberries that have white spots on them due to white drupelet syndrome can be consumed. However, if the white spots are caused due to pest infestation, it is best to dispose of them.
Can pets consume white-spotted Blackberries?
Cats and dogs can consume white-spotted blackberries since they are soft and easy to digest. They do not contain anything that is considered toxic for canines.
Daniel has been a plant enthusiast for over 20 years. He owns hundreds of houseplants and prepares for the chili growing seasons yearly with great anticipation. His favorite plants are plant species in the Araceae family, such as Monstera, Philodendron, and Anthurium. He also loves gardening and is growing hot peppers, tomatoes, and many more vegetables.