Q. I recently had my yard refreshed with a new irrigation
system, new plants, rose bushes and even
a small tree. My roses had suffered badly the last couple of seasons. No matter
what I did, the mealybugs and aphids were victorious. Even if my roses
bloomed they were small and quick to wilt.
I had the landscaper change the soil this time and added
wood mulch to the bed. The leaves as they came in were fantastic. Gorgeous
colors and so full. Then came the first
signs of the aphids. My landscaper told me to get some ladybugs in the Spring,
which I did. They seemed to do the trick for a while, then, came the bites in
the leaves and a return of the aphids (if not in as great abundance). Finally,
before my buds even opened it looked as if they had been burned at the edges.
When they opened, the black peppered the edges of the petals.
 |
| imidacloprid |
I’m not a great gardener but I love these roses and had
real hopes for them this season.
A. From your description it sounds like Western flower
thrips damage. They attack the petals of flowers before they open and cause
browning and wilting of flower buds. You can apply Spinosad for some organic
control but you will have to apply it multiple times about a week apart to get
any kind of control.
Orthene sprays will work to some degree as well.
Another
product to try is an insecticide that contains imidacloprid in the ingredients.
One such product is at Viragrow and probably some nurseries as well.