Definition - What does Starter Plugs mean?
A starter plug, or starter plant plug, can be defined as a small, compact mass or sample of a solid growing medium that is used mainly for seed germination and rooting cuttings.
Gardeners can add their seeds or cuttings to empty plant plugs, or they can purchase plugs that already contain seeds. Likewise, starter plugs can be purchased or homemade.
In horticulture, starter plant plugs provide just the right aeration and moisture control for the successful reproduction process (propagation) in plants. Seed starter plugs are mainly made up of peat and other organic materials. However, there are also rockwool cubes on the market that are small squares made of stonewool, in addition to soil cubes, which are made up mostly of conditioned soil.
MaximumYield explains Starter Plugs
Starter plugs are inert, spongy structured pockets made up of composted pine pulp, peat, and other organic matter.
Starter plugs have a convenient hole on their tops that can be opened by squeezing the sides of the plug. Once you open the hole, you just need to drop your seeds down the hole and tear off a small piece from the top and gently cover the hole to prevent the seed from drying out or washing away after irrigation.
A few important points to keep in mind is that starter plugs are difficult to hydrate once they dry out. So, you need to monitor their moisture levels closely. Growers can also add two or more seeds to a plant plug, as not all seeds are likely to germinate.
Once seedlings begin to grow in plant plugs (often indoors or in protected domes to start), they are planted in the ground or transplanted to larger containers without being removed from the plug.