So you’ve bought some seeds from the nursery or have been given some by a friend. The problem is, you’re not sure what you do next.
This blog is aimed at novices, with tips and information; but there may be something new for the rest of you too. In fact we’d welcome your tips added as comments if you’re an ‘old hand’. We also have a ‘how to’ video on Plews YouTube channel so you can see how a novice got to grips with some seed sowing indoors.
The growing media (GM) needed for sowing seeds doesn’t require much compost in its mix; seeds within their shells have most of the nutrients they need for initial growth. More important is that they don’t rot, so a GM for seeds should be free draining. I would suggest using John Innes No 1 which is a tried & tested seed compost mix (not a brand), or mixing your own GM using multi-purpose compost (peat free of course), horticultural/ sharp sand or horticultural grit and vermiculite in a ratio of roughly 2:1:1.
Half-size and quarter-size seed trays are useful for sowing smaller amounts of seed. If it’s available space that’s at issue, by sowing the seeds in a pattern of alternate rows, ie a row of five, a row of four, a row of five, etc, so they can be sown closer together, you can get a fair few seeds into a half tray.
All members of the pea and bean family, whether ornamental or edible benefit from growing in root trainers: these are basically tall seed pots or trays. As a cost effective and recycling note, the inner tubes of loo rolls and kitchen towel work well as a homemade alternative and can be planted directly into the ground with your seedling as they will rot away.
Size of seeds:
If sowing indoors to transplant later, cover smaller seeds with vermiculite rather than the growing media; it allows air & water to easily reach more delicate seeds.
Really small seeds, such as carrots, are easier to sow if you mix in a little fine sand with the seed; mix in a small dry pot or envelope if you feel they’d stick to your palm; gently tap out the seeds along the line of soil or compost; this also helps you to remember where you’ve sown.
Larger seeds such as sweet peas and beans can be placed in cells individually, or in twos or threes depending on the size of pot. Generally speaking they should be planted to a depth of no more than twice their size.
Most seeds need only light, air (oxygen) water and warmth to germinate, although some do have more complicated requirements to break dormancy. Instructions will be on your seed packet, but basically, keep the growing media damp and warm and look forward to seeing those little green shoots.
In order to retain the moisture in the compost and the surrounding air and to reduce watering requirements, most seeds germinate best if the tray is covered with a clear lid. These can be bought at the same time as your seed trays and half seed trays and is in effect a mini greenhouse. Adding a layer of newspaper under the drip tray on which your seed trays are placed also helps by providing an extra insulating layer.
Remember: label the seeds as you sow each tray or row, with name & date; it’s easy to forget!
Seed sowing indoors can be a very pleasant occupation when it’s raining, hailing and snowing outside…