Chill Hours: This is the number of cumulative hours an apple tree needs to be in an environment at a temperature under 45 degrees F in order to flower the following spring. Some apple trees need only 400 chill hours; others need 1,000.
Grafting: Joining a portion of one plant (in this case, an apple cultivar) to the root of another. Most apple trees are propagated by joining a particular apple cultivar with another compatible apple tree root. The rootstock determines the size and disease-resistance of the young tree, and the scion, or cutting, determines the variety of apple that will grow. Apple trees are propagated by grafting because they do not produce true to seed.
Rootstock: The base and root portion of a grafted plant. The rootstock determines the size of the plant. Many apple trees are grafted onto dwarf rootstock for growing in small spaces.
Scion: The cutting taken from a tree to graft onto the rootstock. The scion determines what variety of tree will grow.
Union: The connection of the rootstock to the scion.
General gardening terms:
Antioxidant: A substance that inhibits damage to the body caused by the release of free radicals. The anthocyanin in blueberries is considered a powerful antioxidant.
Bacillus thuringiensis: A natural pesticide useful against a number of pests. BT is common soil bacteria that have been used as microbial insecticides for the last century. They can be used on foliage, food storage facilities, soil, or water environments. BT occur naturally, affect very specific insects, and are relatively inexpensive and safe for humans, birds, fish, and most beneficial insects. However, for them to work effectively, you need to know what type of insect you want to target and make sure that you buy a strain that will kill that particular species.
Biennial: Plants that form leaves in the first growing season, and flowers and seeds in the second growing season. After that, the plants die.
Brassicas: A genus of plants in the mustard family that includes cabbage, broccoli, Brussels sprouts, cauliflower, kale, and mustard—foods rich in vitamins and minerals.
Borage: A plant with blue flowers that grows wild in some areas. Its leaves, flowers, and stalks are edible and taste a little like cucumber. Borage leaves are good in salads, yogurt, or cream cheese mixtures, or go well when served with shellfish.
Cultivar: A cultivated variety of a plant produced by selective breeding. A cultivar may not produce true-to-seed. Growers who want to retain the characteristics of a cultivar in future plantings should propagate new plantings from cuttings.
Cultural care: Good cultural practices include providing plants the best possible growing situation: proper spacing, watering, staking or trellising, sanitation, mulching, fertilization and general maintenance practices.
Dormant: This is the period of time when a fruit tree’s buds are relatively inactive. This is also called the overwintering stage.
Extension service: A service that extends information to users including farmers, growers, and homeowners. The Cooperative Extension Service (CES) is a publicly funded research and education network linking the resources of federal (U.S. Department of Agriculture), state (land-grant universities), and local (county) governments. Google “extension service” to find your local service.
Free radical: An especially reactive atom or group of atoms with one or more unpaired electrons. Free radicals produced in the body by biological processes (breathing, digesting, exercising) or from the environment (tobacco smoke, toxins, pollutants) can cause damage to cells, proteins, and DNA by changing their chemical structure.
Fungicide: A specific type of pesticide that controls fungal disease by specifically inhibiting or killing the fungus causing the disease.
Grafting: This is a horticultural technique used to join parts from two or more plants so that they appear to grow as a single plant. In grafting, the upper part (scion) of one plant grows on the root system (rootstock) of another plant.
Hod: A portable trough, often used for carrying gardening supplies and materials around your garden.
Horticultural oil: An oil-based pesticide mixed with water that is made of some type of mineral or vegetable oil and is safe for use on food crops
Nasturtiums: A genus of about 80 species of annual and perennial herbaceous flowering plants that are often used as edible and decorate items in culinary dishes. Nasturtiums are sometimes used as companion plants for biological pest control, repelling some pests, acting as a trap crop for others and attracting predatory insects. Nasturtium plant varieties include Alaska, Black Velvet, Empress of India, Orchid Flame, and Purple Emperor.
Neem oil: A naturally occurring pesticide found in seeds from the neem tree. It is yellow to brown, has a bitter taste, and a garlic/sulfur smell. It has been used for hundreds of years to control pests and diseases.
NPK: The three numbers on fertilizer represent the percentage of nitrogen (N), phosphorus (P), and potassium (K) that compose complete fertilizers.
Perennial: Plants that grow for more than two growing seasons.
Perlite: An amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently. When in pebble-like form and mixing with gardening soil, perlite makes for a great aerating and moisturizing agent, as well as providing well-drained soil.
Plug: A section of a plant cut out using a circular tool like a golf hole cutter or a bulb planter. This gives you a cutting of the plant that includes part of the root system. Most commonly used with wild lowbush blueberry plants.
Pollination: The process of transferring pollen from the male part of flowers (anthers) to the female part of the flowers (stigma). Pollination is most often accomplished by insects—primarily bees.
Propagation: The process which grows new plants from a variety of sources, such as seeds, cuttings, and other plant parts
Pyrethrin: Pyrethrins are a class of organic compounds normally derived from Chrysanthemum cinerariifolium that have potent insecticidal activity by targeting the nervous systems of insects.
Rhizome: An underground runner or stem of a plant that stores extra nutrients and eventually develops roots and stems identical to its parent plant. This allows the plant to spread out.
Self-fertile, Self-fruitful, self-pollinating: Plants that do not need pollinators in order to reproduce. Self-pollinating plants have flowers with both male and female parts.
Self-sterile: A plant that needs a second plant of a different variety with which to cross-pollinate.
Soil pH: A measure of the acidic or basic (alkaline) level of soil. Blueberry plants require acidic soil in order to thrive; a pH of 4.0 to 4.8 is ideal for blueberry plants. A neutral pH (neither acidic nor alkaline) is 7 on a 14-point scale.
Soilless growing medium: Common soilless growing mediums include peat moss, perlite, vermiculite, and sand.
Spade fork: A gardening tool that looks like a broad-tined, short pitchfork; used to turn soil and mix with compost and other soil mixes.
Spinosad: A natural substance made by a soil bacterium that can be toxic to insects. It is used to control a wide variety of pests including thrips, leafminers, spider mites, mosquitoes, ants, fruit flies, and others.
USDA Plant Hardiness Zones: The standard by which gardeners and growers can determine which plants are most likely to thrive at a location. USDA has a zoned map, based on the average annual minimum winter temperature, divided into 10-degree Fahrenheit zones.
Variety: A group of plants selected for particular characteristics and which usually produces true-to-seed.
Widger: A spatula-like gardening tool for lifting plant seedlings without damaging them.
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