The Q&A Archives: Changing color of roses over a 4 year period

Question: About 4 seasons ago, my landscaper planted 5 knockout rose bushes. They have been growing fine in a sunny area. During the first two years the roses were mainlt dark red, but the last two seasons, even though the plants seem vigorous and healthy, the roses are getting lighterin color. They are now pale pink or mostly white. Is there any additive to bring the color back to red? Like garden sulfur?

Answer: The Knock Out family of roses was started by rose breeder Bill Radler when he crossed seedlings of 'Carefree Beauty' with 'Razzle Dazzle' to create the original Knock Out? rose. The family now includes varieties that range from blush to vibrant red, and even yellow. Some Knock Out roses are grafted and others are grown on their own root stock. I think yours are the grafted kinds and the vigorous root stocks are overtaking the grafted tops of your plants. The pale pink or mostly white flowers are evidence that the root stock is outgrowing the grafted dark red rose. The soil pH or nutritional level has nothing to do with the rose color so there's not much you can do to restore your roses to their original color other than to trace each stem down to the main stem and cut away those with the odd color flowers to give the red flowering stems more room to grow. Eventually you can get rid of the paler colors with selective pruning.

« Click to go to the homepage

» Ask a question of your own

Q&A Library Searching Tips

  • When singular and plural spellings differ, as in peony and peonies, try both.
  • Search terms are not case sensitive.

Today's site banner is by Char and is called "'Diamond Head' Sunrise"