To Sow Direct or into Trays/Pots for later Transplanting?
With flower seed you generally get a better germination rate by sowing in trays or pots to transplant latter, as you can control the conditions better (moisture, seed depth, temperature, pests). Sowing directly into a garden bed there are a number of things that can go wrong (especially if the bed already has established plants in it). For example, people some them and forget to water them (if they get wet and dry out it is not good for the seed viability), the birds scratch up the seed or seedlings, ants pinch your seed (they love the perennial cornflower seed for some reason), slugs and snails eat your seedlings, established plants crowd them out, someone thinks they are weeds and pull them out. There is nothing wrong with sowing direct into established bed but if you do so mark where you sow the seed (with plant tags or a stick in the ground), lay out some snail and slug traps or pellets, water that area until they come up and sing to them as well if you like : )
The plant descriptions include a number at the end. This refers to the sowing instructions, outlined below.
No.1 Fast germinating seeds (eg. Centaurea) Raise in trays or sow direct into garden. Cover seeds thinly, keep moist and warm, about 20C (very fine seeds do not need to be covered, but press firmly onto soil with a flat board). Best sown in spring and summer.
No.2 Sow direct (eg. Poppies) into garden position from late summer until early spring.
No.3 Cold germinating seeds (eg.Eryngium) Ideally sown in late summer and autumn in a container. Cover seeds thinly and keep them moist and warm around 20C for the first 4 weeks. For the cold period of the next 4-6 weeks put container in the fridge or leave outside in winter at -4 to 4C. Keep container in a shady, cool spot and slowly raise temperature after germination has started.
No.4 Warm germinating seeds (eg. Cobaea) Allow these seeds to germinate under very warm (22C or more) and moist conditions. Best sown in spring and summer.
No.5 Hot water treatment (eg. Acacia) Use sandpaper to slightly damage the seed shell. Then put the seeds in a glass jar and pour boiling hot water over the seeds. Let them soak over night and plant into single pots the next day. Cover the seeds with soil (of the same thickness as the diameter of the seed) and keep them moist and warm at 20C.
No.6 Sow as soon as possible (eg. Waratah) and raise seeds in deep trays or sow in individual pots. Cover seeds thinly, keep them moist and in a shady and warm place (20 to 22C).
No.7 For long germinating seeds (up to 12 months; e.g. Paeonia). In late summer and autumn stratify the seeds in large pots (place seeds in layers of moist sand) and keep them outside in a shady position. Check regularly, especially in spring if germination has occurred, and if so, transfer seeds directly into single pots. Keep moist and shady.
No.8 Large hard shelled seeds (eg. Lupins) Use sandpaper to damage the seed shell and leave in water over night to make seeds swell. Cover the seeds with soil (same thickness as diameter of seed). Keep moist at 20C.
No.9 Erratic Germinators (eg. Arthropodium) Sow in trays and cover seeds thinly; keep moist and warm around 20C. If germination has not occurred after 6 weeks put seed trays outside in a cooler position. These seeds are best sown during the colder months in early autumn.
No.10 Large hard shelled seeds (eg. Lupins) Use sandpaper to damage the seed shell and leave in water over night to make seeds swell. Cover the seeds with soil (same thickness as diameter of seed). Keep moist and cool 5-8C. Not suitable for tropics.
The following Salt Zones are referred to in the plant descriptions:
Zone 1 - most exposed of sea coast gardens
Zone 2 - plants are able to tolerate some salt in the soil and deposits on leaves
Zone 3 - most protected areas with wind breaks