A Better Boxwood

When it comes to determining if you have a better plant, it is essential that you know and understand the plants that are currently available. New plants must be trialed and compared in side by side tests with the best varieties to know what you have. If you can’t beat the best, then you better keep breeding until you get it right.

This side by side comparison of boxwood is a great example of the power of trialing plants. I’ve been growing and trialing North Star boxwood for over five years. When we first got the plant from its originator Gary Katerberg I was skeptical that his plant could rival the best boxwood varieties available. In fact, I did not give it much of any chance of being introduced. But when we had it in a test bed with twenty other varieties of boxwood, it preformed so well, the results could not be ignored. When you see it side by side with Green Velvet, the number one variety on the market, you can clearly see that it is a better plant. Even during winters with temperatures as low as minus 15 degrees, North Star boxwood shined; the winter and the spring foliage color was so much darker. While Green Velvet turned a pale pea green, North Star boxwood remained very dark. Additionally the plant is very compact, with dense growth, yet at the same time it grows faster than other popular varieties.

Clearly “Seeing is Believing,” and side by side trialing is the only way to find out if a plant is truly better or not. North Star boxwood has passed the test.

A Tale of Two Roses


Just outside my office, growing side by side, are two excellent roses. Both are very free flowering and bless me with a continuous, summer-long display of red flowers. Each rose remains as clean as a whistle without the aid of sprays or chemicals. I suspect you're familiar with one of these roses. Perhaps you even grow it? It was developed Bill Radler and is called Knock Out.

But this is the story of the other rose. Its name is Candy Oh! Vivid Red and most likely you’ve never heard of it before. It was not developed by Bill Radler, however, it would not exist but for this well known rose breeder of the North.

At ripe old age of 13 David Zlesak read an article in the Milwaukee Journal that changed the course of his life. The article was about Bill Radler and how he hybridized new roses. Fascinated by the article and the idea of creating new plants, Zlesak wrote to Radler. To his surprise, Radler wrote back and this letter was the spark and inspiration that started David Zlesak on his plant breeding career and ultimately resulted in the rose Candy Oh! Vivid Red.

While working towards his PhD in plant breeding, David worked on numerous crops including small fruit, potatoes, Easter lilies and various perennial plant species. His first big breeding breakthrough came in 2006 when Proven Winners introduced Tuscan Sun Heliopsis a remarkable dwarf, continuous flowering perennial. Yet even though David found success in breeding other crops, his passion for roses never ceased - nor did his rose breeding. While other students were going to fraternity parties, David was up in his dorm room growing on thousands of rose seedlings under florescent lights. Out of these seedlings he selected the healthiest 1,500 plants and grew them out in garden plots he rented from friends and neighbors. Out of these, he selected the 50 healthiest, most floriferous plants. His selection process was further aided by the harsh Minnesota winters and the ubiquitous rose disease – black spot. Only the hardiest, most disease resistance roses remained.

Out of the thousands of seedlings that started out in his dorm room, David found that one seedling, a polyantha hybrid that stood out from all the others. It was vigorous, healthy and very floriferous. The vivid red flower color was so intense that it seemed almost to smolder in the summer sun. In 2008 David Zlesak introduced his first commercial rose selection - Candy Oh! Vivid Red.

That is the tale of two roses, and how Bill Radler had a hand in the development of both plants.