the secret to healthy seedlings please

At what stage do they look sick?

It's likely to be either:
- too much or too little water
- lack of nutrients
- lack of light

For the water -- take care watering, making sure the soil is moist but not waterlogged.

For the nutrition - use fresh seed compost, thin out as your seed packet instructs, and transplant to potting compost before it's spent.

For the light - make sure the seedlings get enough sunlight (but not so much that they dry out!).

IFollowing on from Ukslim, if you leave them too long before you prick them out, they will get leggy because they will be competing with the other seedlings in the tray. You have to guage the right time to thin, transplant - and choose the strongest looking seedlings. Don't be afraid to lose some if they look feeble!

I agree with spritzhenry ,thin out and pick the best ,leggy shoots are no good to no-one and remember if youre first seed crop fail ..THE LATER YOU PLANT ,THE LATER YOU PICK especially with weather now ..I mean to say only at Xmas I had geraniums flowering and I am in SOUTH YORKSHIRE ..if flowers can veg can Im sure GOOD LUCK .

I agree, leave them too long before pricking out and you get leggy seedlings, thin out and leave the strongest is the best way. However they have a habit of going leggy just when you have turned your back on them for a minute.

If your seedlings are leggy when you prick them out just make the hole you are putting them in in your seed tray a bit deeper. As long as the leaves are not actually touching the soil you should be ok, it will encourage them to make more roots and the base of your plant will become stronger as it grows.