I cut this milk jug almost in half, used a knife to poke several holes in the bottom, filled it with moist soil, added some seeds and then taped it all closed. Four months later it was bursting with plants.
But I often buy milk in opaque jugs so I tried a different method. I decided to use empty containers and shrub pots so the plants would have more room for root development. It worked extremely well.
I filled this big pot with soil and added a few branches I'd pruned from my Rose of Sharon. Bamboo stakes work extremely well, too. Many seeds require a period of cold stratification, which happens automatically with winter sowing.
Using a $2 plastic drop cloth and some bungee cords, I cut a piece of plastic large enough to cover the pot.
I secured the plastic with a cheap bungee cord and poked holes in it with the screw driver. I used the lighter to make them a bit bigger but you could skip this step and just use your finger and a sharp stick or a pair of scissors.
The plastic heats up the interior while also protecting the seedlings from wind and wildlife. It's essential to cut holes in the plastic to allow rain to enter. The plastic can be reused each year.
When a winter storm caused the bamboo stakes to burst through the plastic, I topped each stake with a ping pong ball to keep the plastic from ripping any further. It worked extremely well and I can use the balls from year to year.
The pot in the front was full of ammi majus seedlings while the one in the back had rudbeckia.
I recovered the pots with plastic and let my mini-greenhouses work their magic.
I bought the ping pong balls super cheap at Amazon.com.
By early April, I had lots of malva seedlings!
Malva 'Zebrina' is also called French hollyhock. The pollinators love it.
Linaria 'Fairy Bouquet' is a cool season annual that was my first winter sown plant to bloom.
Once it's done blooming, I pulled it out since it would fry in our summer heat, anyway. I replaced it with some winter sown curly parsley.
All types of rudbeckia have high germination rates using this method.
Rudbeckia hirta 'Irish Eyes'
Ammi majus is commonly grown in England but rarely used here. It's a beautiful but very short lived annual that looks similar to Queen Anne's Lace but isn't invasive. Ammi is the white flower.
Once it's done blooming, I pull it and let other plants fill its spot. The pollinators and beneficial insects love it.
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