Spring has arrived! Have you decided what food you are going to grow this coming year yet?
I started sowing the seeds using my propagator 3 weeks ago. There are many propagators in the market, ranging from £3 to £70. The one I use is self-watering and only cost around £7 from Homebase. This means that I do not need to water everyday- more time for myself! The most expensive range is usually self-heating. I do not see much point splashing out on one though as I found the seeds germinate just happily if I keep the propagator somewhere warm. Here is what the propagator looks like:
(diagram by Homebase)
The propagator is very easy to use. I started by putting water in the hole so that the mat is touching the water properly. This draws water up to feed the cells.
This propagator has 40 cells, which means it can germinate 40 seeds at the same time. To ensure each cell is fully utilised, I usually put two seeds in one cell when their size is small. (Note: Make sure they are as far away from each other as possible, with equal amount of compost around) This is because sometimes only one of them germinates. Of course there are times when both do. In theory, the weaker (ie. shorter or thinner) seedlings should be removed so that stronger one could grow even better. However, I usually go against this ‘rule of thumb’. Being petite in build myself, I get all philosphical and believe the short and weak should be given an equal chance to live. So I tend to separate their roots and plant the seedlings into bigger pots once they are more developed. And they usually grow just as well!
Depending on the species, seeds generally take 7-10 days to germinate when the propagator is kept in the dark. Once the plants start to touch the top of the transparent plastic cover (called greenhouse cover in the diagram), I remove the cover and put the propagator in a nice, warm and sunny place indoor. Seedlings tend to grow towards the light source. This is how they look like after a day of ‘sun bathing’ by the sliding door of my room- they all ‘pointed’ towards the garden side.
I highly recommend rotating the propagator daily early in the morning or in the evening by 180 degrees to keep the plants growing straight.
2 important tips :
1. The propagator has cooridnates which is definitely good to use. It is hard to identify which one is which as the seedlings do not look like the adult plants! I usually write the plant names down on a grid (see above)
2. The best compost to use is John Innes seed compost. It has the right formula to keep the seedlings developing healthily. If the compost is too rich in nutrients, the seedlings would grow too tall to fast. They become tall and weak. Of course, if it does not have the right balance of nutrients, the seeds simply do not germinate.
Winkypedia 
I actually use a propagotor as the “next step”.
My preference is to germinate the seeds beforehand between 2 sheets of wet kitchen roll and then transfer to the propagator after you get 0.5-1cm growth developing. (You can keep the wet kitchen roll in a propagator to keep them warm and fast track the germination).
In this way, you can see if the seeds do germinate and get rid of any that dont make it. What I used to find (when I did it your way) is that some times, the seeds dont actually germinate/grow and then go mouldy and wipe out the healthy plant.
Rockwool is another way to go……… especially if you want ot germinate high value seedlings .
Thank you for sharing your tips!
Interesting point about potential mould problem. I have not experienced it but not that you have mentioned it, I will keep a close eye!
I read about the pre-propagator germinating process before but I found seedlings of 0.5-1cm tall a little delicate to handle. Any tip for the transfer?
use a straw!
No, seriously, McDonalds straws are quite good for this:
– get one straw and cut it into smallish sections
– use one bit and push into the soil and lift up at a slight angle (this removes a “plug” of soil). Keep it in the straw
– get a second bit of straw and scoop up the seedling and roots (make sure its still a bit moist) and it would just slide in
– drop it into the bored out plug hole (gentle tap or even blow slightly)
– replace the bored out soil from above and gently press down
– drop or two or water
A lot of work if you’re doing loads of seeds……….. but I find that it definately makes a differece. Also, keep the seedling in the small container for as long as possible……. the idea is to allow the plant to form a dense and compact root ball….. resulting in a much more stronger plant overall.
Have fun!
Thanks for the tips. Very creative adaptation of McDonalds straw! It sounds a bit like surgery, which also requires great precision for a delicate situation!
I agree. It is important to let the root develope in the compost. It makes further transfer that much easier!
What a good article and I like Davids method. Am I right in thinking the tiny seedlings are then put into the heated propagator, but how long for ?
My greenhouse is unheated but my heated propagator is in it.
I am worried about allowing the seedlings to become chilled after I take them out of the propagator.
My propagator gets very wet inside and the cardboard cells are going mouldy, do I need to open the vents and keep them open ? any advice please.
I have just started propagating my seedlings in a Stewart’s heated propagator it cost £12 from wilkinsons, it just warms up very gently and stays at the perfect germinating temperature , it’s my first time but so far so good , I have used grow sure seedling & cutting compost , then john inns multi purpose for potting on stage when they are bigger. I will keep you all posted with the results . Good luck everybody