64 Basic Perennial Garden PlantinG & Maintenance
IDENTIFYING THE PROBLEM
The next step in pest control is identifying the pest and determining if it’s truly a
problem. Too often, insecticide or fungicide is grabbed and sprayed on the plant
without a clue as to the real problem. I have had perennials such as ‘Silver
Brocade’ beach wormwood (Artemisia stelleriana ‘Silver Brocade’) and copper
fennel (Foeniculum vulgare ‘Purpureum’) completely eaten by what appeared to
be just some caterpillar. It turned out to be butterfly larvae. Artemisia stelleriana,
along with species of Anaphalis (pearly everlasting) and Antennaria (pussytoes),
are host plants of the American lady butterfly; fennel feeds black swallowtails in
the East and anise swallowtails in the West. Several other perennials are favored
caterpillar food: hollyhocks of painted lady butterflies, rue (Ruta graveolens) of
giant swallowtails and black swallowtails, and milkweeds (Asclepias spp.) of
monarchs. This demonstrates the importance of proper identification of the
so-called pest in question. The plants may look a little rough at times, but who
cares when it means more butterflies in the garden? Perennials usually recover
from damage with fresh basal growth anyway, either that same year or the
following season.If we want beauties like these
visiting our gardens we need to
pay the price of some damage
by their larvae.