Answer: Vermiculite is fairly inert, so there's nothing that might inhibit the germination of your seeds, however the particles are large, making large air spaces between the particles. Even though you water when you think the vermiculite is dry, you may not be keeping the medium as moist as the seeds require. A better choice would be a sterilized seed-starting mix that is specially milled to provide just the right balance of solid particles and tiny air spaces between the particles. Seed starting mix retains water well and provides traces of nutrients to newly emerging roots. After planting your seeds, cover the pots or trays with plastic wrap to help hold in moisture. Remove the plastic as soon as the seeds germinate to avoid damping-off disease. Seeds need moisture and warmth more than they need light to germinate, so place the pots or trays on the refrigerator or other reasonably warm place until the seeds sprout, then move them to a brightly lit location. Following the above tips should produce healthy seedlings.
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