➤Cold frame A box-like structure or frame, usually made of boards, “with a removable glass or plastic top.” It sits outside on the ground and serves, among other purposes, as a miniature greenhouse (with no artificial heat) for hardening off transplants. Seedlings in a cold frame can be protected from cold temperatures and wind, or exposed to outdoor conditions, depending on whether the lid is open.
➤Foot-candle A unit of measurement of light intensity. “A unit of illumination… equal to that given by a source of one candela at a distance of one foot (equivalent to one lumen per square foot or 10.764 lux).” (Google Dictionary.) Relevant if you are starting transplants indoors and need to provide artificial light. 5,000 foot-candles is adequate for starting most transplants. (Gough)
Here are approximate amounts of foot-candles produced by various sources, for reference:
.02 – the moon
20-30 – indoor reading light
4,000 – noon sun, midwinter
10,000 – the sun at full intensity ”on a clear mid-June day at noon in the eastern and midwestern states” (Gough)
12,000 – the sun at full intensity “in some desert and tropical areas” (Gough)
➤Four-inch pot Good for holding individual transplants. Seeds can also be sown directly into these pots, or seedlings can be transplanted up into them from smaller containers like jumbo packs. (Avoid sowing seeds directly into pots larger than four inches in diameter across the top, as the larger pots may become waterlogged.) Sow 2-3 seeds per 4-inch pot and thin later, keeping the healthiest seedling. (Gough) Generally speaking, each four-inch pot holds somewhat more than enough growing medium to support a healthy transplant up to the stage when it is ready to be planted outdoors. (Gough)
➤Hardening off A process of gradually transitioning your seedlings from the indoor to the outdoor environment, usually over a period of a week or so. During this period, plants are gradually exposed to sunlight, outdoor temperatures, wind, etc; while also gradually receiving less “pampering” (lesser and lesser amounts of water and fertilizer.)
Nebraska Extension Educator Sarah Browning provides this deeper insight into what is happening during the hardening off process: “The goal of hardening off is to cause plant cell walls to thicken, changing soft, succulent growth to firmer, harder tissue.” (Browning) Browning goes on to ennumerate changes a plant goes through while being hardened off. Some of these changes involve actual hardening, i.e.”natural waxes on leaf surfaces thicken as plants are exposed to more sun, reducing the rate of water loss,” and “cell walls develop more lignin to strengthen them.”) Other changes also contribute to the “toughening up” of the plant: Top growth slows, root development speeds up, the amount of water in cells is reduced (making plants less susceptible to freezing,) and “the amount of carbohydrates (stored food reserves) in plant tissues increases.” (Browning)
➤Jumbo pack (a.k.a. cell pack, 6-pack) A multi-celled container for holding several seedlings of the same type of plant. Each cell may be about 2 inches across the top, more or less. Good for holding smaller to intermediate transplants.
➤Peat pot/ peat pellet Seed-starting containers made of biodegradable material. Peat pots/pellets can be planted along with the seedlings they contain. Designed to avoid root disturbance and the resulting transplant shock that often happens when seedlings are moved out of their original containers to be transplanted up into larger containers or out into the soil. Bear in mind that peat pots planted into larger pots or into the ground must be kept moist to biodegrade.
➤Root ball “The mass formed by the roots of a plant and the soil surrounding them.” (Google Dictionary)
➤Seeding flat (aka seeding tray) A tray, often divided into a number of small individual cells, that can be filled with soil or growing medium to start transplants from seed. Should have drainage holes. Good for holding the youngest/smallest transplants. Aim to start about four plants per inch. (Gough)
➤Transplant (v.) To replant in a different place. (n.) A plant that will be moved or has been moved to a different place. For various reasons, the seeds of some plants must be sown somewhere other than where the mature plants will be located. For example, tomato seeds are often sown indoors, and the resulting seedlings are raised there for a time before being moved outside to continue growing to maturity. This is because the period of ‘tomato-friendly’ weather outdoors is generally too short to allow directly sown tomatoes to produce fruit.
➤Tray Placed beneath a seeding flat, container, or collection of containers, for support and to catch draining water.
Gough, Robert and Cheryl Moore-Gough. The Complete Guide to Saving Seeds. North Adams, Massachusetts: Storey Publishing, 2011.
Browning, Sarah (Nebraska Extension Educator.) “Hardening Off Isn’t Hard.” Nebraska Extension in Lancaster County. Article updated April 2015.
“Cold frame” definition. Google Dictionary.
“Foot-candle” definition. Google Dictionary.
“Root ball” definition. Google Dictionary.