Propagation & Growing Essentials

Surprisingly little — seed compost, modules or small pots, a clear cover (a propagator or even a plastic bag), a warm spot, and water. A heated propagator widens what you can grow and improves germination of trickier seeds, but is not essential. Even a sunny windowsill with a cling-film cover will start most seeds successfully.

For most cottage garden flowers, no — a warm room or sunny windowsill provides enough warmth for hardy annuals and many half-hardy varieties. A heated propagator becomes essential for tropical and subtropical plants: chillies, peppers, aubergines, basil, and similar species that need consistent 21-26°C soil temperatures to germinate.

Module trays (where each seed has its own cell) are generally easier than open seed trays — plants suffer less transplant shock when moved on, and you can prick out without disturbing neighbours. Open seed trays work well for very small seeds where you scatter and thin later. Most gardeners use both depending on the plant.

Damping off is the fungal disease that fells seedlings at soil level. Prevention is everything: use fresh compost (not last year's spent stuff), water from below where possible (stand pots in a tray), ensure good air circulation (remove propagator lids once seedlings emerge), and avoid overcrowding. Affected seedlings rarely recover.