Cactus seeds not growing

[beginner]

I planted the following cactus seeds in a small covered tray:

Using the following mix:

The tray has been on the window for about 6 weeks now and there is no sign of any growth.
I Planted at start of December, I am out of the house a lot so the heating is off and the house is fairly cold as I live in UK.
The soil is moist.

Is it time to write off these seeds? Any tips as to why they have not grown?

 

[Chuck]

Soil temperature is very important when sprouting any seeds. You need a heat mat and possibly a grow light. I would also press the seeds slightly into the soi but not bury them.

 

[beginner]

Is it too late to add heat map and light at this stage?

 

[Chuck]

Is it too late to add heat map and light at this stage?

It is probably but not definitely too late. I would plant more seeds alongside those already planted and that, along with a heat mat and light, you should be sucessful.