Playing with growing radish indoors under lights while there is too much snow outside yet. Plants are starting to bulb up, but the borders of the leaves are turning red. Any soil doctors out there with solutions? Thanks
It could be a phosphorus deficiency...especially if it's mostly under the leaf or you notice the green of the leaf going to a green/blue hue along with the red.
That would be my guess too. Are they cold? Some plants have a difficult time absorbing P if they are young and to cold. It happens to a few of my annuals every year if I plant them out a to early. They recover when they warm up.
The little critters aren't cold. 70F Thought I might add a photo for clarification
Here is a link that might be useful: Lively Dirt - The Garden Blog
Those look like beets to me.
No - the leaves are clearly rough and lobed at the bottom of the leaf blade, unlike beets. They're just discoloured radishes.
Have they had any fertilizer? I ask because the pale color often says "We need nitrogen."
Looks like low P to me too, notice it's on the older leaves?