Just a few points of interest, as my Sungold and Zenith tomato plants are quite the most vigorous I have ever grown.
1. I sowed on April 7th, soon after new moon, rather than my traditional close to full moon. This was more pragmatism than principle, associated with when the full moons fell!
2. I transplanted 8 day old seedlings not into JI No.1, rather straight into garden centre own-brand MPC.
3. 11 days later, I was obliged to pot on into 15cm pots as the plant growth was so vigorous.
I have sown other open-pollinated strains which are also very vigorous, not quite as quick to germinate as the F1 seeds.
Obviously, we had a whole week of hot and very sunny weather, which helped tremendously.
But I am minded to say that buying lots of different successional composts seems unnecessary and that sowing at any time during the waxing moon phase may be pretty effective.
I tried loading photos up, but sadly they are too large to be accepted.