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Alright then, walk this way, no not that way this way.
First I work on the KISS, I "love rock n' roll", no not that one, the Keep it Simple Sally principal, so just grab some Seed raising mix(SRM) and bung it into your empty container of your choice.
Following the KISS principal I going to plant some Cos lettuce. Cos there so easy. Hah ha ha ha, Oh I kill myself sometimes.
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Found one.
Now just a few notes
* Your SRM should be moist at this stage, not dust dry or tea bag out of your cup of tea soggy.
* When putting your SRM into your container don't squash it in tight just fill it up and give your container a bit of a tap and level off the top.
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Here's on I prepared earlier.
After you will need to put a planting hole in the top of your SRM. Some people use a pencil, I use my finger. The required depth for Cos seeds is 3-5mm so just a divot with said finger and place one seed in each hole.
Some times you'll get advice to plant 2 seeds in each divot but I only want 3 seedlings for my garden so I'm sure of at least 50% strike rate.
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If you want a 100% strike rate you'll probable get it with fresh seed but if you want to be sure then you can pop 2 seeds into each divot and when they germinate just carefully pull out the weakest one.
Now all that is left to be done is to cover the seeds to the required depth either by putting some extra SRM over the seeds or as I do just push the edge of the divot over the seeds.
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Just a few things left, I always label my seedlings cos I will forget which is which.
Water the punnet. I use half strength fish emulsion for the first watering and after that never let the SRM dry out and don't over water.
I usually water when just the very top of the SRM is just starting to look like it's drying.
I also place the seeds in a well lit but shady area (dappled sunlight under a tree is good)until the seeds have been up for a week or so and then gradually introduce them to full sunlight and by then they should be ready to plant into your nicely prepared garden soil.
A rough time line. End 1 week, seeds of cos lettuce should be up by now and can be watered with another half strength fish emulsion.
End 2 week, seed should be 25/30mm tall and growing well.
End week 3, another half strength fish emulsion. Almost getting full sun
End week4, whack em into the garden, again, with another half strength fish emulsion.