Summer Flowers: Tips for Sowing indoors
The summer season is often too short for many of our loveliest flowering plants, which need months to grow from seed and come into flower. Since the spring is frequently too chilly to cultivate them outdoors, give them a headstart by sowing them indoors shown below.
- Use a propagator with a transparent cover and put the seed trays inside it.
- There should be holes in the bottom of the trays; if there aren’t any, make some. It should be possible for the soil to absorb moisture from below.
- Use special seed compost or cocopeat. The sowing medium should be germ-free to prevent the rapid development of molds and algae.
- Break up any lumps of compost and remove impurities. Stringy bits of peat will otherwise cause damage to roots when you are planting out.
- Firm the top of the compost to provide a flat surface over which the seed can be distributed evenly.
- Don’t use any force when firming the soil - it should remain aerated. Oxygen is very important for plant root.
- Stand the try in a dish or in the base of the propagator and pour water into it. The water will then be drawn up into sowing compost.
- You will know that the soil is well saturated once the surface fells moist.
- While the soil is absorbing water, use the time to write the names of the species you intend to sow on labels. Use rot-resistant labels and a pencil or waterproof felt-tip with non-fading ink.
- If you have bought packets of seed, check the dates to see how long they are capable of germination. Don’t use old seed.
- Pour the seed into the palm of your hand. If you sow it straight from the packet, it will rarely be spread evenly in the seed tray.
- Scatter the seed very evenly over the surface, or over a part of it, if you want to sow several species in the same tray.
- Sowing the seeds at least 1/2 in apart will make subsequent pricking out much easier.
- Insert the appropriate label close to the seeds. This will let you tell at a glance which seeds are coming up where over the coming months.
- To avoid subsequent pricking out, use a multicell tray. Sow larger seeds either on their own or with one other seed in each cell.
- Insert large seeds at a depth three times their own thickness unless the instructions on the packet suggest otherwise.
- Cover the seeds in the tray with a very thin layer of compost or fine grit. A colander of sieve will help to distribute it evenly.
- Seeds needing light to germinate should not be covered. The relevant information is included in the alphabetical section of the book.
- Seeds should be kept moist during germination. A cover or sheet of glass will ensure constant atmospheric humidity.
- Seeds sown on the surface are particularly at risk of drying out and the vents of a propagator should therefore be kept close.
- Place the propagator in a light position at room temperature and protect it from harsh sunlight by placing a newspaper over it.
- Once all the sown varieties are showing signs of germination, the vents may be partly opened, initially and subsequently kept fully open.
- The cover should be removed as soon as most of the seeds have germinated. Don’t put the seedlings in too warm a position or their growth may be stunted.