MissyWeitzel These tubers I just dug from one area look terrible, but they aren't rotten. Others in a different bed don't have the dark brown splotches. I cut several to check for rot and the insides look normal. What would cause this and will the tubers be more susceptible to rot over winter? Thanks for your help.
Cosey MissyWeitzel Tubers can get infected with a host of fungi and symptoms can look similar to symptoms in potatoes. I would sacrifice a tuber (hopefully without an eye) and cut a couple of cross sections through the tuber making sure to cut through an area with the spots and one without. If you see anything, post a pic. If there is no discoloration to the inner part of the dahlias it would suggest it's purely superficial. If you see any decay, discoloration, or brown inner ring it's most likely a fungal infection and won't survive storage. Here is an external link with good photos. https://potatoes.ahdb.org.uk/disease-defects
blown_dry MissyWeitzel I agree with Ted. My soil has lots of clay and coffee grounds and compost. The tubers totally get brown stains. I mean, they are in dirt and all. 🙂
Teddahlia My best guess is that the bed with the dark spots has lots of compost and organic material and as it decomposes it stains the surface of the tubers. To be sure, I would use cinnamon on the tubers. Obvious rotten spots can be removed and cinnamon applied over the wound. When you grow in very sandy soil with no compost at all, the tubers have no blemishes. However, watering and feeding the plants is more difficult in sandy soil. I just take what nature deals me and that includes some blemishes
MissyWeitzel Teddahlia thanks so much Ted that makes a lot of sense now that I think of it. I have very sandy soil, but the area where these were growing had a bunch of wood mulch that was mixed in from when I got rid of a raised bed nearby. I left it mixed in because I'm trying to increase organic matter but I think I'll go through and get the larger chunks out. Thanks again!!
MissyWeitzel Cosey thanks so much. I sliced up two of the worst looking ones and the insides look normal. I appreciate your suggestions! My tubers are usually pretty darn nice looking so these clumps had me stumped. Hopefully it really was just discoloration from the wood mixed in the soil. If anything unusual happens with these over winter I'll post here.
Cosey Cut into the stem and see if you have a brown line or ring in the plants. Also look up Verticillium Wilt in potatoes/tuber. I see light brown streaking in these tubers. If I see this at dividing they never survive storage. I would store separately.
SteveM When I see that it is usually at the end of a drip line where the plants get extra (too much) water. I never noticed amy problems in storage if the brown is only skin deep.
Cosey I'm beginning to wonder if I get all the pleasure of experiencing all the random oddities that can happen to tubers. I'd like an easy year this year! 😆 Every season I'm diagnosing some weird pathogen that is causing rot.
