Fielding Questions: Rose pruning, fruit tree pollination, evergreen recommendation
Don Kinzler answers questions about the best time to prune a rose bush and cross-pollination. He also gives a reader a recommendation for an evergreen tree that won't grow taller than 25 feet
Q: I’m new to rose growing and planted a rose bush for the first time last summer. I didn’t prune the rose in the fall, and I’m not sure how far down to prune it now. — Joy M.
A: Roses are among my favorite plants, and it looks like yours wintered well. Roses are best pruned in the spring, because fall pruning leaves open wounds that can contribute to greater winter dieback.
Your rose is relatively young, so pruning this spring can be lighter than future years. Begin by pruning back any canes that are winter-injured. There’s a sharp demarcation line between blackish brown winter-injured cane portions and the lower green part that’s still alive. Yours looks to have survived nearly to the tips of most canes.
Rose bushes bloom best on young, vigorous growth. Such growth is stimulated by pruning, which is why roses are best pruned severely every spring. Prune back the rose bush by at least one-half in spring before leaf-out and remove weak, small-diameter branches.
Roses are heavy feeders, meaning they respond well to the nutrition provided by fertilizer. Options include water-soluble types and granulated. Some are tailored specifically for roses, which is probably preferred, but all-purpose flower fertilizer is also effective. Fertilize in early May and again in early June. Good luck with the rose, and send me photos in bloom!
Q: I want to add fruit trees to my yard, and we’re especially looking at Toka plum, Superior plum, Golden Spice pear, Ure pear, and Sweet Sixteen apple. All the tags say the trees needs a pollinator. In researching what that means online, it could be anything from bees to a second tree. Can you answer what it means for a tree to need a pollinator? If a second tree is needed as the pollinator, is it better to get the same variety or different? — Dana C.
A: Bees do the job of pollinating fruit trees, so they’re always needed, but when a tag says a pollinator is needed, they mean another tree. Apple, plum and pear trees need to be pollinated by a different named cultivar of the same fruit type. For example, your Toka and Superior plums will cross-pollinate each other successfully. Your Golden Spice and Ure pears will cross-pollinate.
Your Sweet Sixteen apple, however, is left without a pollinator. It must be an apple of a different named cultivar. Another Sweet Sixteen won’t work, and plums and pears won’t pollinate apples.
If there’s an ornamental flowering crabapple in the area, they’re closely related to apples and serve as great pollinators. Maybe a neighbor has a different apple variety. The trees don't need to be within the same yard, but preferably within a block or two. If you have room for another apple tree, Honeycrisp or Haralson would accompany Sweet Sixteen well.
Q: We had a very tall, old spruce that died and was taken down. After having a tall and lanky evergreen, we’re in the mood for a shorter pine. Do you have any recommendations that reach no more than 25 feet at maturity? — Melanie N.
A: I’ve got just the thing, and I know you’ll be happy with it. North Dakota State University, in its Woody Plant Improvement Program, developed a beautiful pine called Prairie Statesman Swiss Stone Pine.
Prairie Statesman Pine is an elegant, stately evergreen that develops a strikingly dense growth habit. The needles are rich emerald green with silvery blue overtones. It’s extremely cold hardy and drought tolerant, which makes it an outstanding specimen evergreen for landscape planting.
In time it can reach 30 feet, but that's close to the 25 feet you mentioned. Although you won’t find Prairie Statesman at every garden center, I’ve seen it offered at many, especially those locally owned, and it’s well worth a little searching.
If you have a gardening or lawn care question, email Don Kinzler, NDSU Extension-Cass County, at email@example.com . Questions with broad appeal may be published, so please include your name, city and state for appropriate advice.