Have you noticed that some of your raspberries have white spots? There are a few possible reasons why this happens, but most likely it is White Drupelet Syndrome. What is this disorder? Should we be worried about it? How to prevent it? All our answers in this article!

“White Drupet Syndrome” in raspberries :

Indeed, the most common reason for partial discoloration in raspberries is “white drupet” syndrome. It is not a disease, so there is no danger to your crops. It is simply an insolation of the fruit that occurs especially during heat waves! Berries that have full exposure to hot afternoon sun are more susceptible to this disorder because the hot, dry air allows more direct UV rays to penetrate the fruit. Higher temperatures and even wind can also trigger this reaction. Note that even a raspberry with unsightly white spots is still perfectly edible.

“White Drupet Syndrome” in raspberries – Photo: Alsagarden.

Preventing your raspberries from a heat stroke !

To avoid this little problem in your harvest, avoid planting your raspberry bushes in areas that are too sunny and are subject to hot summer winds. It can also help to orient your rows in a north-south position to minimize the effects of blazing afternoon sun and thus sunscald fruit.

Keep in mind that in its natural environment, the wild raspberry occupies the glades rich in humus and appreciates the light shade of beech, mountain ash and elderberry which support each other thanks to the mycorrhizal fungi. At the base of your raspberries, spreading RCW (fragmented ramial wood) as mulch also increases vigor and resistance to disease and sunburn.

In the most extreme cases and for crops already in place, setting up a shade cloth can also be a solution.

Lucas Heitz, The Curious Gardener

Landscape gardener and geographer, I am passionate about the plant world and its countless curiosities. Founder of the Alsagarden blog and activist for gardening in harmony with Nature, I am also a French gardener, fervent defender of Heritage varieties.