One of the most common requests when I am in the roses helping people is for fragrance. A second request in our area is mildew resistance.

A few years ago I was down at Weeks Roses looking over the new roses with Tom Carruth that were in their breeding program. Tom has been a friend of mine for a number of years since he started as a salesperson before starting their new rose program. Over the years he has been very successful with several notable AARS winners.

As we were going down the rows we were talking about how this rose had a terrific color but no form. This rose bloomed heavily but the color was just so-so. That rose looks nice but finished ugly. He was talking about some of the problems breeders have getting that perfect rose and fragrance came up.

He commented on some linkages in rose characteristics that suddenly explained a lot that I had seen but never really put together. The first linkage was between fragrance and mildew susceptibility. All of a sudden I saw why Mister Lincoln, Chrysler Imperial, Tropicana, and almost all lavender roses seem to get mildew. As I review the top 10% in fragrant roses in my mind they all have more susceptibility to mildew then most of the good non-fragrant roses.

Mister Lincoln Rose by Jungle Jim

I can tell that isn’t the only reason roses get mildew but the fragrant roses are still chosen because of the fragrance. This also seems to be true in the Antique Roses. If a rose gets mildew and isn’t fragrant there isn’t much that can make it distinctive enough to be worth planting. Leonitas and Black Baccara are exceptions because of their distinctive color.

If you want fragrant roses you need to keep in mind the cultural practices that can reduce mildew.

1) Keep them in full sun.

2) Space them well for good air circulation. Mildew grows in high humidity conditions.

3) Overhead water in the morning. Yes, I said overhead water. Mildew dies in presence of actual water drops.

4) Prune out actual mildew to prevent spores from spreading.

Fragrant roses are wonderful and now you know why rose breeders can’t give you the perfect fragrant disease proof rose.

---