Careful watering is also required to keep the blocks from disintegrating. But watering with care is always necessary when starting plants from seed. Too little, too much, too forcefully there are plenty of ways to go wrong. With a capillary waterer, absent-minded gardeners need only fill a reservoir now and then to ensure that a consistent, gentle flow of moisture is delivered to seedlings. These systems usually take the form of a channelled tray and a porous mat on which seed containers sit.
Water gets wicked up through the mat to the pots to keep the soil moist.
Some models include a gauge to keep tabs on the reservoir s water level. Tabletop propagator Don t confuse them with mini-greenhouses or propagators, which usually consist of only a tray and a clear dome. With pots or peat pellets thrown in, they re called greenhouse kits or growing kits. Besides inconsistent watering, another suspect in poor germination is fluctuating temperatures. An electric heating mat heating wires sandwiched between layers of rubber matting placed under the flats provides gentle radiant warmth to the root zone.