Spots on potatoes, pruning shrubs and moss rose quandary
Q: What are the white spots on our russet potatoes that I recently dug? Are they still edible? — Marie Talley, Oxbow, N.D.
A: Thanks for the interesting photos. The white lesions on the tubers are symptoms of a disorder called lenticel spot. Lenticels are the natural breathing pores of the potato tuber which usually go unnoticed — until they’re disrupted. Potato Grower Magazine describes the situation and cause well.
"Lenticel spot is a common physiological disorder that occurs when lenticels enlarge. Potato tubers are living organisms, so when they are unable to obtain sufficient oxygen, the lenticels enlarge to acquire more. When soil is waterlogged for a period of time, the lenticels enlarge and can appear like small white popcorn on the tuber surface. When the enlarged lenticels dry, they may resemble small scab lesions. Another condition that causes reduced oxygen availability, and thus leads to enlarged lenticels, is soil that is highly compacted."
Put bluntly, the potato tuber’s lenticel breathing pores opened wide in an attempt to get oxygen while nearly drowning in this year’s saturated soil. The potatoes are fine to eat, but the enlarged lenticels can cause the tubers to have a reduced storage life.
Q: Our bushes desperately need trimming and I was hoping to do it before we leave for Arizona. Considering the cold weather we’re having, can I trim now? — Jim W., Casselton, N.D.
A: I have good news: You can relax, as there’s no need to trim shrubs in the fall. In fact, there’s not really any advantage to prune this time of year, and it might carry some risks.
Sometimes in our fervor to tidy up the yard and garden for fall, we feel like we should be trimming overgrown shrubs. I’m a strong advocate for waiting until spring to prune shrubs while they’re still dormant and before the buds begin to swell and open. Fall pruning leaves open wounds, and I’ve noticed fall-pruned shrubs are more prone to branch dieback, possibly from moisture loss and desiccation through cut branch ends, especially during test winters with strong winds, frigid temperatures and lack of protective snow cover. Delaying pruning until closer to spring reduces the risk. You now have one less task before heading south.
Q: Last year, our moss roses were colorful and beautiful. This year they reseeded themselves by at least 1,000 percent, but we were so disappointed when every single one of them bloomed white. What happened? — The tenants at Mission Court, Ada, Minn.
A: Thanks for the fascinating question. Moss roses, also called portulaca, are one of the annual flowers that seed themselves readily, and lend themselves to planting in their own little flower bed space so they can emerge the following spring undisturbed. As a boy, I remember our neighbor in Lisbon, N.D., grew moss roses in a small square flower bed surrounded on all sides by sidewalk, and they arose each spring from seed shed by the previous year’s flowers.
Why did yours all bloom white? In many annual flowers, white is a predominant color, often more vigorous than other colors. For example, when planting different shades of petunias, I use only one white petunia plant for every two or three other colors to prevent the vigorous white from outcompeting the rest.
The white moss roses in your original mixture likely produced seed more rapidly than the other colors, dropping a larger quantity of viable seed. The other colors might not have produced any viable seed, or in a lesser amount, and when all seedlings emerged the following spring, the predominant white had won the survival-of-the-fittest battle.
If you have a gardening or lawn care question, email Don Kinzler, NDSU Extension-Cass County, at firstname.lastname@example.org or call 701-241-5707. Questions with broad appeal may be published, so please include your name, city and state for appropriate advice.