Slug Deterrence Tests
Conducted by Lex Buford
Mr. Buford owns property that abuts City of Portlands
Forest Park, the largest wilderness park within the city limits of a US city.
Mr. Buford is a former US Forest Service biologist and is
knowledgeable about flora and fauna surrounding his property. Due to the amount of forest
cover and vegetation, there is a heavy slug presence in and around Mr. Bufords
property. Mr. Buford gardens extensively, growing many of his familys vegetables and
ornamental flowers. He composts, uses organic growing methods and controls all products
used on his property. especially commercial fertilizers and pesticides.
Goal: To determine if perlite is a slug deterrent to
Experiment: Two distinct garden areas were set up to
observe slug damage that occurs routinely during the gardening season.
- Vegetable Garden: Tilled in composted wood chips and perlite
into large planting area so that soil approximated 1/3:1/3:1/3. perlite:woodchips:soil.
Area planted with spinach, lettuce, tomatoes, squash and corn.
Garden was raked and "washed" to insure that perlite particles
were present on the soils surface.
- Flower Garden: Area was top dressed with perlite after
planting with hostas, dahlias, spiderwort, cannas. red-hot pokers, tulips and gladiolas.
Plants emerged through the perlite. which remained on the gardens
surface. during growth.
Observation: With perlite used either as a top
dressing or soil amendment, little slug damage occurred to either garden. Under normal
circumstances, the plantings suffer seasonal slug damage without some sort of control. The
vegetables and ornamental flowers are favorite slug foods. No chemical controls were used
to protect plantings.
Slugs were present in areas around the gardens but did
little damage to plantings in either garden. The slugs stopped before entering the gardens
and did not slime over the perlite to access plants. It appears that slugs were adversely
affected by perlite. which proved to be an effective slug deterrent in the garden.