Radish brown spots!!

Asked July 6, 2017, 12:04 PM EDT

We are growing radishes in our garden for the 1st time(we only recently moved here!)and now we are harvesting them,some when we cut them open we find some have a brown patch with a couple of small holes in!! Does anybody have any idea what is causing it please?By the way we live in the United Kingdom!

Outside United States

3 Responses

Thanks for your question. It is difficult to diagnose your radish problem without photos of the plant. Obviously the existence of holes in the root point toward an insect. Both the onion maggot (known to be in the UK) and the cabbage maggot eat radish roots. Their damage looks similar; I have attached a photo of a cut-open radish with cabbage maggot evidence.

As the latter article describes: "Cabbage root maggots overwinter as small brown pupae in the soil near roots of fall brassica crops where the larvae fed. Adults emerge in spring and can travel up to a mile in search of host plants. Eggs are laid in the soil at the base of the stem of host crops. Cool, moist soil conditions favor survival of the eggs, and soil temperatures that exceed 95°F in the top 2-3 inches will kill them. Larvae feed on roots and pupate in the soil. A late summer flight (late August, early September) may damage fall root crops. There are 3-4 generations per year in central New England."

This article also outlines cultural, chemical and biological controls. I do not know which of the chemicals are available in the UK, nor which can be used by home gardeners.

If this is not descriptive of the damage you're seeing, you're welcome to write back with photos. Thank you!

Many thanks for your response,from the photo you sent,it looks identical to our problem,now we can look at getting rid of them,once again many thanks

You're most welcome. Happy gardening!