[A Reyt Tayty]

I've done 2 sets of toms. One lot just in individual pots, they others with a plastic cup over the top of the individual plants. The ones without pots are in a room with a slightly higher temp than the ones under propogators and are doing well. The ones in the cooler room with propogators set off slowly, but are now catching up nicely. In fact, I think some may be getting a bit leggy. Light is good, so it's not that. How long should you leave the propogators on? Just while the plant is very small, or is it ok to leav them on for longer?

[JayG]

If there is too much warmth for the amount of available light legginess is inevitable.

You can't do much about the light (apart from using DD's aluminium foil reflector trick) but you can turn off the propagator - the fact that your other plants are growing more steadily is the clue to the answer really.

[DD.]

Your eyes often think that light levels are good, but they adjust.

I find using foil is an absolute necessity, even in a well lit window, after all it only comes in from one direction.

[Poolcue]

Once the seeds are up I remove them from my propagator.

[A Reyt Tayty]

Thanks chaps. It's not the light. I have a bank of three a4 sized cards covered in tinfoil at the back of both sets of plants. They grow as straight as a die, no pulling to the light whatsoever. BTW, it's not an electric propogator, just a clear pot inverted over the seedling.

I've also noticed today that the plants which have developed decent true leaves are  withering slightly at the tips. Could my compost be running out of nutrients?