This year I planted the usual potatoes and about half way through the season the leaves started to close up and had brown edges. When I dug them up the potatoes were marble size or smaller. I plant in a different place each year. Can you help?
It’s great to hear you are rotating your crops. However, there are a number of other factors that could be contributing to your poor potato harvest. Firstly, it could be from poor quality tubers or seed potatoes. Were they purchased or leftover from the kitchen? All potatoes purchased from garden centres are known as certified seed potatoes - they are guaranteed to be healthy, true to type, and heavy cropping.
Secondly, while potatoes can be cultivated successfully in both light and heavy soils, it’s critical that the soil is well-drained. Heavy, waterlogged soils can lead to poor crops and often the death of the potato plant.
When the young plants are growing, the soil should be mounded up around the plants. This helps support the plant, protects from blight and prevents the tubers from turning green in the sunlight.
Another reason could be from lack of moisture during the growing season which can lead to lighter crops and smaller sized potatoes. However, also avoid overwatering. Mulch with pea straw to help retain moisture in the soil around the plant.
Finally, your soil might be lacking sufficient nutrition to produce good crops of potatoes. Fertiliser should be incorporated into the soil two weeks before planting the potato tubers. Use a specific potato fertiliser like Daltons Garden Time Potato Fertiliser which is ideal for growing good quality potatoes.