What is the cause of yellow/brown appearing on raspberry plant leaves?
Hello, I recently bought this raspberry plant and repotted it with some standard garden compost. I've noticed in the last couple of days the leaves lower down are going yellow and showing brown patches. The leaves at the top of the plant currently seem ok. What's the cause?Very much looking forward to getting your response! Thanks Clare clare
Certified GKH Gardening Expert
Raspberries are very difficult to keep in container, unless they are a cultivar that is meant to do so. Now, I'll tell you all of the things that I have to do to my blackberry plant, which is its close cousin, to keep it in a container.
I have to constantly feed, correct pH, and repot to fresh soil when it compacts itself. This will be once or twice per year. While you are at it, you will want to trim off some of the larger roots, and the bottom 1/3 of the small roots. This will allow for Those smaller feeder roots to grow again. You do not want those big stability roots in container.
Next, you will want to trim the longest canes by half to keep them manageable at the same time. It is best to time this just after fruiting to avoid damage to next year's fruit.
Next, you will want to keep dolomitic lime handy, as well as iron sulfate. Dolomite lime will keep the pH as steady as possible while correcting the magnesium issue that it is experiencing now. That is the coloration between the veins that you are seeing. The Iron sulfate will correct a common iron deficiency, as well as keep the soil pH from getting too high as the plant takes nitrogen out of the soil. Add both once or twice per year as needed.
Make sure that you compost is cut with a potting mix to lighten it up a bit.
Unfortunately, raspberries are very finicky in container, and without proper care will only last a year or so.
I will provide our list of articles on the subject of raspberries for you to sift through. It will offer loads of information that will be helpful to you. Here is the collection: https://www.gardeningknowhow.com/edible/fruits/raspberry