A structure that allows you to grow more than one variety of tomato or cucumber side by side, but its compact design doesn't take up much space in the garden.

To incorporate an organic or mineral material such as compost, rock powder, sphragnum peat, fertilizer, or lime into the soil to enhance its fertility or structure, or adjust its pH.

Examples of Soil Amendments:
Compost: See definition of compost.

Aged Manure: This soil amendment is great for vegetable growers. It consists of composted animal manures (usually from farm animals) and possesses all of the qualities of good compost: high levels of organic matter, good nutrient- and water-holding potential, dark color, and no offensive smells.

Earthworms: Earthworms are beneficial for a number of reasons. As they tunnel through the soil, they create air pockets and space behind them, introducing better air and water movement into the soil. As they chew through leaf litter, their excrement (known as vermicompost) consists of round aggregates of soil particles held together by slime produced by bacteria in the worm's stomach. These round aggregates of soil are packed with organic matter and nutrients, all of which are immediately available for plants to use.

Green Sand: Green sand is a very useful soil amendment. Mined from marine deposits, it gets its color and name from its high amounts of potash (a source of potassium). It also helps loosen clay soils, and aids in water and nutrient retention. Green sand contains many trace elements as well. It works as a slow-release amendment, so a little bit goes a long way.

Mulches: There are many benefits of mulching. Mulch insulates the soil, protecting the plants from extreme temperatures. It prevents soil from eroding away with storm water or wind and conserves precious soil moisture that otherwise would evaporate. Types of mulch include pine-bark mini nuggets, pine-soil conditioner, pine needles, straw or hay, shredded cedar mulch, wood chips, composted leaves, and buckwheat hulls.

A plant, such as a tomato, that is genetically programmed to complete its full life cycle within one year. That is, the seed germinates, then the seedling grows into a mature plant that blooms, sets seed, and afterward dies, all within the space of one growing season.

To suddenly sprout a stem and bear flowers, often in response to heat or drought. When lettuce, spinach, and other cool-season greens bolt, the leaves become tough and bitter, and the crop must be replaced.

Though bulbs, corms, and rhizomes are often used indiscriminately, the terms denote different types of underground storage structures. A bulb (such as a daffodil or onion) is a bud enclosed in layers of leaf bases; a corm (crocus, gladiolus) is a swollen section of stem; a rhizome (bearded iris, daylily) is a horizontal stem. The exact type of storage organ determines the way in which the plant is divided or otherwise propagated.

A lightweight tray of molded fiber or, more often, plastic that is divided into many small sections like a muffin tin. Commonly used to hold potting mix for starting seedlings in a greenhouse or under lights indoors.

A mixture of natural elements such as grass clippings, coffee grinds, and vegetable peels that decomposes and provides a constant source of fertilizer and soil conditioner for your plants. Compost also helps make soil more absorbent, reducing the need for watering. Learn how to make compost. 

Cultivated variety; a superior type of some plant species selected or bred artificially and maintained through inbred seed or by cloning (propagation by division, cuttings, grafting, etc.). Any plant name enclosed in single quotes (e.g., 'Chiogga' beet) denotes a cultivar.

A wooden planting tool with a pointed end that makes a small planting hole for seeds, seedlings, or small bulbs.

The beginning of growth for a seed; its first sprouting.

Full-spectrum fluorescent lights that can be positioned directly above seeds and raised as seedlings grow. Grow lights not only provide the light required for healthy development, but they also warm the soil, speeding germination.

The characteristic appearance of a plant, stem, leaves, or other organ (including size, shape, color, pattern of growth, etc.).

Able to withstand the extremes of the local climate. Most often used to describe a plant's tolerance for cold, but may also denote tolerance for heat or drought.

Heirloom vegetables are open-pollinated plants that have been cultivated for at least 50 years. They are often more flavorful, colorful, and interesting than hybrids, but they may be challenging to grow if your soil is disease-prone.

A nontoxic pesticide, this powdery substance actually has sharp edges that kill slugs and bugs without chemicals in your vegetable garden.

A stable form of organic matter derived from the decay of plant and animal materials; a vital component of garden soils.

Hybrid plants are the result of crossbreeding to produce offspring with desirable traits, such as disease resistance or uniform color or size. As a result, hybrids will not usually reproduce true to seed, and new seeds must be planted each season.

Scientific shorthand for nitrogen, phosphorus, and potassium, the three nutrients used in greatest quantity by plants. The three-number formula (5-10-5, 20-20-20) on fertilizer labels identifies a product's NPK content.

Open-pollinated (OP) plants have parents of the same variety and reproduce true to seed, so their seeds can be saved and replanted and the resulting plants will resemble their parents.

Term used by gardeners to distinguish those sorts of soil amendments, fertilizers, and pesticides that derive from unprocessed natural products, as opposed to products chemically synthesized in a factory. Examples of organic products include manures, rock phosphate, and rotenone, an insecticide extracted from the roots of a South American plant; synthetics include ammonium nitrate, superphosphate, and malathion. 

Note: To gardeners, the terms "organic" and "natural" mean products derived from a plant, animal, or mineral source, not those containing USDA-certified organic materials (which includes DDT).

Collars of heavy paper that are pushed into the soil around a plant to keep pests at bay. They are removed once the threat of infestation has passed.

Any garden flower that dies back to the ground after it blooms or at the end of the growing season and sprouts anew the following spring. One example is asparagus.

A light, porous, granular material produced by heating and expanding volcanic rock. Water absorbent, but sterile (without plant nutrients), perlite is used to increase the drainage and improve the aeration of potting soils, and as a rooting medium for cuttings.

A measure of acidity or alkalinity; in gardening, usually applied to soils. A soil's pH may range from 0 to 14, with a pH below 7 indicating acidity, and a pH above 7 indicating alkalinity.

A detailed plan that lists what is planted in each bed so that proper crop rotation can be maintained from year to year.

To transplant from a container, or from indoors, into the garden.

There are many types of potting mixes, and they all have their advantages. They are defined by the composition of ingredients. 

Soilless: These store-bought varieties (also called sterile mixes) contain no soil from your garden. They are predominantly sphagnum peat moss.They are ideal for seedlings because they eliminate the risk of unknown elements that can prey on young plants. 

Bulb-Forcing Mixes: This mix contains some grit and is optimal for bulb vegetables such as onions and garlic. 

General Mixes: Comprise a balance of organic and inert matter. General mixes, of course, are blended to accommodate the widest range of plant needs.

A self-supporting heap of soil that has been raked to a level surface. It also can be enclosed in a frame of timbers, or low brick or stone walls. Because the soil within raised beds has been thoroughly dug and in general heavily amended, it typically offers a nearly ideal texture and high-nutrient value. As a result, it promotes better plant growth and higher yields of flowers, vegetables, and fruits.

The mass of roots and soil exposed when a plant is slipped from its container or burlap covering or dug out of the ground for transplanting. Root bound is a term that is used when roots are densely tangled or coiled around the root ball; a condition often seen in plants grown too long in a small container.

To change the location each year (usually in a 3- to 4-year cycle) in which a particular vegetable crop is grown, to reduce the threat from soil-borne diseases.

A light, permeable material, usually polypropylene or polyester, that is spread over rows of plants to protect them from insects and/or a light frost. Invaluable in the vegetable garden.

A second planting of vegetables in mid- to late-season.

A young plant.

To bear seeds that germinate without assistance in the garden. A tendency to self-sow may be desirable, as with many kinds of wildflowers, but it can also turn a prolific flower or vegetable into a weed. Self-sowing occurs as a result of dropping seeds or or by a natural action such as wind or water. 

The medium that supports plant life and the source of 13 of the 16 elements that are considered essential to plants. The remaining three  -- carbon,  hydrogen, and oxygen --  are supplied by air and water. 

Types of Soil:
Forest: This biologically rich soil is found just below the layer of leaves in the forest and is high in organic matter/humus. The soil supports a diversity of biology, including earthworms, and has good water and nutrient retention. The soil is dark in color with a loose and crumbly texture.

Sandy: This soil is very well drained, contains little in the way of organic matter/humus, and has little water or nutrient retention. It feels gritty to the touch, does not form clumps or aggregates, and is usually light in color.

Clay: Clay is very dense soil, which easily forms clods or "sausages" between the fingers. It has the potential to hold large amounts of nutrients and water but is often poorly drained and becomes anaerobic (devoid of oxygen). 

Loamy: This is an ideal soil for vegetables, with nearly equal parts sand, silt, and clay. It drains well, is dark in color, and feels loose and workable in your hands. It easily forms larger aggregates and has a good amount of organic matter/humus.

Well-Aerated Soil: Well-aerated soil has plenty of pore space between the soil particles or crumbs. This soil promotes water intake and stimulates root development.

A soil block maker is a device that allows you to make blocks out of lightly compressed potting soil. Soil blocks are a fantastic option for starting your seeds. The roots of the plant will grow to the edge of the block and stop, awaiting transplant -- this means there is no transplant shock, no torn roots, and plants establish themselves quickly.

The act of adding a support mechanism to a plant that has vines and climbers. Stakes direct and contain the growth of a vegetable plant (such as a tomato), keeping their stems from degenerating into messy sprawls. These supports also allow you to stretch space in an overcrowded garden. Stakes are typically made from bamboo.

To pull out or cut off crowded seedlings so those remaining have adequate room for vigorous growth. In pruning, thinning involves the removal of stems and branches from a congested plant to enable more light and air to penetrate into the interior.

To dig or cultivate soil to prepare it for planting.

To spread fertilizer, compost, or manure over the surface of the soil around a growing plant in order to nourish it without disturbing the roots.

A plant's swollen, underground storage organ, a modified stem or root with buds from which new shoots and roots may develop. Potatoes and dahlias both produce tubers.