Acidic: Soil with a pH between 0 and 7.0. Sometimes referred to as “sour” soil.
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. Ex. Lady bugs, praying mantis, lace wings, parasitic wasps.
Biennial: A plant that completes its full life-cycle within two growing seasons.
Biological Pest Control: Using live organisms such as predatory and parasitic insects or pesticides produced by living organisms (bacteria and protozoa) to control garden pests.
Bolting: When onion put up seed head. Occurs when a short day onion is planted in a long day area. In Oklahoma this may occur when onions are brought up from the warm valley in Texas and planted will it is still very cold.
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.
Bulbing: When the top of the onion falls over naturally indicating that in 7 to 10 days it should be harvested.
Chlorosis: A yellowing of leaf tissue due to a lack of chlorophyll. Possible causes of chlorosis include poor drainage, damaged or compacted roots, high alkalinity, and nutrient deficiencies.
Companion Planting: The cultivation of specific plants together in the same area, especially if one species will benefit from another.
Compost: Decayed organic matter used for building soil. It is dark, odorless and rich in nutrients. What the doctor called for as an amendment to Oklahoma’s clay soil.
Cover Crop: Plants grown to protect and build the soil during an interval when the area would otherwise lie fallow.
Crop Rotation: The successive planting of different crops on the same land to improve soil fertility and help control insects and diseases.
Cultivar: A plant variety that has been intentionally cultivated, and improved upon. See “Oklahoma Approved”
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.
Expanded Shale: Pellet sized rock which when mixed with Oklahoma red clay begins to break down the mineral rich clay. Can be tilled into the clay prior to planting.
Fertilizer: An organic or synthetic material, including manure and nitrogen, phosphorus, and potassium compounds, spread on or worked into soil to increase its ability to support plant growth.
Foliar Fertilizer: A fertilizer applied in liquid form to a plant’s foliage so that the plant can absorb the nutrients through its leaves. I use Garrett Juice and have for years!
Green Manure: A crop that is grown and then mixed into the soil to increase soil fertility or organic matter content.
Heavy Soil: A soil that contains a high proportion of clay, is dense and poorly drained, ie Oklahoma’s red clay. The soil is so compact that there is no air between the particles.
Humus: The result of organic material being decomposed into a dark soil-like material that contains plant nutrients.
Integrated Pest Management (IPM): A planned pest control program that takes into consideration all aspects of the garden ecosystem, rather than focusing on a single pest species to be eliminated. This strategy relies on regular monitoring of the pest population to determine if and when to take action. When control is necessary, nontoxic methods (traps, beneficial insects) are used first. Then, if necessary, natural or synthetic pesticides may be employed as a last resort.
Loam: Fertile soil, usually easy to work, with equal proportions of sand, clay and silt and with a high amount of humus.
Macro nutrients: The major elements essential for plant growth. The major plant macro nutrients are nitrogen (N), phosphorous (P), and potassium (K).
Mechanical Control: Hand picking, vacuuming or physically killing pests. Insect traps and barriers are also effective mechanical controls.
Micro nutrients: Mineral elements which are needed by plants in small quantities.
Mulch: Any organic material, such as wood chips, grass clippings, compost, straw, or leaves that are 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).
Oklahoma Gardening Zone:
Oklahoma Winter Hardiness Zone:
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). Adjustments to the PH can be made as follows: To raise the PH add lime (calcium). To lower the PH add sulfur. The idea PH for Oklahoma is 6.5 to 6.8.
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. Order your Oklahoma soil test from your Oklahoma County Extension Agents office. See article on “SOIL TEST”
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 turf grass. A primary goal is to reduce water use.