Top tips for March seedsowing
March 08, 2014
This weekend is blocked out in my diary, - it says seed sowing.
In preparation this week, i've been clearing all the overwintered plants out of the greenhouse. - I've planted out lots of last summer seed sown perennials - Echinops Ritro, Stachys Lanata, Rudbeckia maxima, Delphiniums and Verbenas.
The overwintered sweet peas are planted out in the polytunnel, - so now i've got free space, and free seed trays to sow this years seeds into.
So I thought i'd give you an idea of what I sow into what.
At the beginning of the growing season, I use heated propagators to start off seeds. - This is great for those Half hardy annuals that need a long season to get into flower, - like Cleome, Molucella, Anthirrinums and Scabious. Before now, - i've not had electricity in the greenhouse, so these propagators have been balanced on tables in front of the windows in the house with the most light. - This year for the first time, they've been in full use in the greenhouse for the last 3 weeks.
When it gets to March, and I can start the hardy annuals that don't need bottom heat to get them going - Cornflowers, Ammi, Larkspur and Gypsophila are good examples, - then I start to use seed trays, - The ones with 5 strips in them are great if you want a decent number of anything, - you can sow 20-30 seeds in each strip.
If you're wanting smaller numbers, then a window sill propagator with modules is ideal.
I use lots of these green windowsill propagators, and the inserts last at least 3 seasons (i'm on the 4th season with a few of them) I sow 4/5 seeds into each module. - If you are useing them for saladings (Rocket, mizunas, lettuces etc) then you can just pop each module out into the ground. - if you're using them for flowers, then you can prick out from them into cell trays.
This is my favourite size of tray, - it has 84 modules, and i've got some with 66 modules. They are deep enough that you can get a big enough root system on each seedling that they can be planted out into the soil as soon as the weather is appropriate.
The list of plants that i'm going to be sowing this week includes
Chrysanthemums, Asters, Amaranthus, Stocks, Verbena bonariensis, Calendula, Cerinthe, Euphorbia Oblongataand more Sweet peas.
I sow into my own mixture of seed compost - This post I wrote gives a lot more information about composts, but I've now moved on to a peat free rather than reduced peat mix, using a sieved mixture of organic municipal waste and a peat free compost.
However there are lots of plants that I won't be sowing for at least another month. - Some don't like root disturbance, some have their growth "checked" if they stay in pots for too long. Either way you want them to be at exactly the right growth rate to put them out as soon as the last frosts have disappeared, Some, i'll wait to sow direct into the soil instead of starting them inside - These include
For direct sowing - Dill, Nigella, Bulplurum and Zinnias
For quick germination and planting out before they get too root bound - Cosmos, Tithonia, Zinnias, and Sunflowers
Hold off sowing them until late April. (or mid May if frosts still look likely)- Which is great, because all the hardy annuals you sow this weekend will be ready to go out by then.
Enjoy the sunshine, and get sowing