When to feed?

I have heard conflicting reports of when to feed. The plants are 13 days old after I dropped them into the soil after germination. They look fine, however two of them have a bit of yellow at the ends and have a very slight wilt. Question, I have Plagron Terra Grow. The recommended dosage is 5 ml (about one teaspoon) per litre. When should I start feeding them? I have heard now because there is a bit of yellow, however I have read some posts stating to wait about at least another week to feed them.

Any help would be great! Thanks in advance.

Peace from Praha!

I started about a week and a half after they were put into the SunShine#4. The clones I got had a few sets of true leaves, with super long roots so they were a bit more mature than some clones that are available on the market. Seems you are growing from seed, so I really can't comment on that. Best of luck.