Garden Glossary

Scarification

Horticulture expert Dr. Lelia Kelly defines the gardening term scarification. Scarification is the process of weakening, opening, or abrading a hard seed coat to allow seed germination. Some seeds will not germinate until the seed coat degrades. The usual method of scarification for the home gardener is mechanical: scraping the seed with a file or knife. Commercially, scarification is also done using acids. 

Surfactant

Horticulture expert Dr. Lelia Kelly defines the gardening term "Surfactant".  A surfactant is an agent that helps chemicals mix better and reduces surface tension to help the chemical adhere to the plant better.  It helps keep the chemical from beading up and running off and is it often a detergent they use to add to a chemical mix.  A couple of drops of Joy for example will get the job done.

Sweet/Sour Soil

Horticulture expert Dr. Lelia Kelly defines sweet and sour soils. These are terms used by some gardeners to describe the pH of the soil. Sweet soils are alkaline and sour coils are acidic. This term originates in the days of the westward expansion. The pioneers would taste the soil to find the best place to grow crops.

Systemic

Horticulture expert Dr. Lelia Kelly defines the gardening term "Systemic".  Systemic usually refers to how pesticides move through the plant.  If you have a systemic insecticide it means it is soluble enough in water that it can be taken up through the tissue of the plant and translocated throughout the plant to protect It against disease.  Herbicides like Roundup which are systemic do that as well.