Acidic: Soil or compost with a pH between 0 and 7.0. Sometimes referred to as “sour” soil by gardeners.
Alkaline: Soil with a pH between 7.0 and 14. Sometimes referred to as “sweet” soil.
Annual: A plant that completes its full life-cycle within one growing season.
Beneficial Insects: Insects that eat or lay their eggs in other insects thereby controlling them. Used in this country since the late 1880’s they are the best known form of biological control.
Biennial: A plant that completes its full life-cycle in two growing seasons. It produces leaves in the first and flowers in the second.
Biodynamic: Made popular by Austrian philosopher Rudolf Steiner, biodynamic farming combines organic methods, including crop rotation and composting with special plant, animal, and mineral preparations and the rhythmic influences of the sun, moon, planets, and stars.
Biological Pest Control: Using living organisms such as beneficial insects or parasites to destroy garden pests.
Botanical Insecticides: Derived from plants, these organic pesticides provide a powerful “knock down” to a large number of pests. They leave no residues and breakdown quickly in the environment.
Chlorosis: A yellowing or blanching of the leaves due to lack of chlorophyll, nutrient deficiencies or disease.
Companion Planting: The sowing of seeds in the garden in such a way that plants help each other grow instead of competing against each other.
Compost: The end product of the decomposition of organic matter and biodegradable materials by aerobic and anaerobic microbes is known generally as compost. Compost is nutrient rich since during the decomposition process the larger organic compounds are broken down into their basic elemental particles that are easier for plants and other organisms to absorb. Compost serves as a great growing medium for agricultural and horticultural purposes as well as a soil conditioner. This dark brown to black soil/mulch can be easily made in the kitchen or back yard in a compost container or the more traditional pile form.
Cover Crop: Vegetation grown to protect and build the soil during an interval when the area would otherwise lie fallow.
Crop Rotation: The planting of a specific crop in a site different from the previous year.
Cultivar: A plant variety that is cultivated, not wild.
Cultural Control: The practice of modifying a growing environment to reduce the prevalence of pests. Examples include changing irrigation methods or selecting resistant plants.
Direct Seeding: Sowing seeds directly in the soil where they are to grow, rather than transplanting seedlings.
Double Digging: A process of developing a loose, deep garden bed with good aeration and drainage by first removing the topsoil, then loosening the subsoil, and finally replacing the removed topsoil. Double digging is an ideal form of garden bed preparation when planting carrots, beets, potatoes, onions and other root crops as well as a way to improve the overall health of the garden. The increased oxygen and water penetration from double digging allows worms and microbes — vital to decomposition and plants’ absorption of nutrients through nitrogen-fixing — to thrive.
Fertilizer: An organic or synthetic material added to the soil or the plant, that is important for its nutrient value.
Foliar Fertilizer: A fertilizer applied in liquid form to a plant’s foliage in a fine spray so that the plant can absorb the nutrients through its leaves.
Green Manure: Also known as cover crops, green manure crops are planted when land is fallow, for instance during fall or winter, and used to suppress weeds and bring nutrients to the surface. It is then plowed under before planting in order to increase biomass within the soil. Green manure is often used to recondition soil that has been over worked and is a useful tool in agricultural crop rotation. Legumes such as clover and vetch are popular green manures because they encourage the growth of nitrogen-fixing bacteria that break down nitrogen from the soil and atmosphere into forms useable by plants.
Heavy Soil: Dense soils made of silt and clay that are often very fertile but require soil amendments to improved structure as well as oxygen and water penetration.
Humus: Decayed organic matter usually seen as dark brown or black soil. Humus refers to organic material that has reached a point of stability in which it can decay no further. Fully-finished compost is humus. It is rich in nutrients and makes for a very fertile growing medium. Humus comes in different varieties depending upon the decomposed material that makes it. These varieties are very commonly used as soil amendments. Topsoil is an example of humus found nearly everywhere.
Integrated Pest Management (IPM): An effective and environmentally sensitive approach to pest management that relies on a combination of common-sense practices. IPM programs use current, comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control methods, is used to manage pest damage by the most economical means, and with the least possible hazard to people, property, and the environment.
Loam: An ideal soil for gardening and agriculture made of a combination of sand, silt and clay in roughly equal proportions. Loam is high in nutrients and humus and is able to retain more water than other soils while still allowing it to flow freely. Loam may come in different varieties usually described by the different proportions of constituent particles such as sandy loam, clay loam, silty loam, or sandy clay loam, etc. Gardeners often create loam from their existing soil with the use of soil amendments and compost.
Macronutrients: The major elements essential for plant growth. The major plant macronutrients are nitrogen (N), phosphorous (P), and potassium (K).
Mulch: Any organic material, such as wood chips, grass clippings, compost, straw, or leaves that is spread over the soil surface to hold in moisture and help control weeds.
No-Till Gardening: A type of garden that calls for no cultivation of the soil after the initial tilling. Instead, regular mulches are added and plants are planted through the mulch. This saves on labor and eliminates weeds which might germinate as a result of tilling.
N-P-K: An abbreviation for the three nutrients that have been identified as absolutely necessary for plants – nitrogen (N), phosphorus (P) and potassium (K).
Organic Gardening: A type of gardening based on building a healthy soil through composting and using additional nutrients from naturally occurring sources. The general idea is to feed the soil and the soil will feed the plants. Healthy more vibrant plants are better able to resist insect pests and disease. If control is required, cultural and mechanical methods are used first. A variety of approved pesticides are used only as a last resort.
Organic Matter: Any material that was recently living or produced by a living organism and is capable of being decomposed.
Parasite: An organism that grows, feeds, and is sheltered on or in a different organism while contributing nothing to the survival of its host. Beneficial insect parasites include trichogramma wasps and whitefly parasites.
Perennial: A plant that grows and flowers for many years.
Pesticide: A general term for chemicals used to destroy living things that are considered pests.
pH: A scale from 0-14 which expresses the degree of acidity or alkalinity of the water or soil. A pH of 7 is neutral (below 7 is acidic – above 7 is alkaline).
Predator: As used in horticulture, a beneficial insect that preys upon pest insects. Predators include ladybugs and praying mantis.
Soil Amendment: Material added to the soil to improve its physical properties, such as water retention, permeability, nutrient content, aeration and structure.
Soil Test: A measurement of major nutrient (nitrogen, phosphorous, potassium) and pH levels in the soil.
Sustainable: Capable of being continued with minimal long-term effect on the environment.
Tilth: Often used to describe the general health of the soil including a balance of nutrients, water, and air. Soil that has good physical qualities is said to be in good tilth.
Topdressing: The application of nutrients or soil amendments after the crop has been planted or established.
Xeriscaping: Creating a low maintenance landscape with native plants and reduced areas of turfgrass. A primary goal is to reduce water use.