by Mitzi
Davis
Colorado State University Cooperative Extension
Master Gardener
Larimer County
Q: What flowers can I plant on the south side
of my house for summer color? It’s a sunny, dry area.
A: The following annuals should be fine on the south side as long as they get
some water during the summer: alyssum, celosia, cosmos, gazania, nasturtium,
petunia, salvia and zinnia.
Q: I have ants in the joints of our cement driveway and in the sand
between the bricks in the patio. What can I do to control them?
A: Use boric acid (a disinfectant available at pharmacies) as a tracking powder.
The powder is picked up on the legs of the ants and carried back to the nests.
This is a slow-acting insecticide and will take 10-14 days to kill the ants.
Boric acid is relatively non-toxic, but keep all chemicals away from children
and pets.
Q: There are round “bites” taken out of the leaves of my
roses. What is causing this?
A: It sounds like leaf-cutter bees are eating your roses. The bees rarely sting
humans and are important pollinators of legumes and other garden plants. The
damage they do to the plants does not significantly affect the health of the
rose bushes. If you are exhibiting your roses you can cover the bushes with
floating row covers.
Q: What is Neem oil? I’ve heard it is a safe, organic insecticide.
A: Neem oil is a botanical extracted from the seeds of the neem tree. The active
ingredient azadirachtin acts as a growth regulator that interrupts the insect
growth cycle causing death to larval and pupal stages. It provides effective
control for whiteflies, mealybugs, thrips, aphids, leaf miners and others. It
is also effective as a fungicide for control of foliar diseases like powdery
mildew. It can be toxic to bees if applied while bees are active.
Gardening and Insect Fact Sheets are available on-line by clicking HERE.
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