I have always thought a small seed in a larger container has issues with
water-logging. Not enough root growth to deal with moisture. Small seed cells
will dry out faster getting water when they need it by observation.
In a small cell it is more obvious when they get good root growth and get
thirsty. Good root growth can handle the moisture and feeds the green growth
above the soil.
Also a Realestate/space issue. If I have room for 12 tomato plants, I sow at least
8-10 seeds per variety. In a 36 cell 1010 tray. Three cells per variety. Then cull
at about 3-4 weeks. One per cell. The most strong and healthy. I then have three
plants of those 12 varieties. Insurance. If all goes as planned, I have my 12 and
I have extras to gift to friends and family.
(I grow hundreds but the basic formula works for me)
I did a germination test over the holidays, (I grow year round indoors)
testing seed starting soil, etc. They did so well I continued and now have some
early tomatoes that I'm just potting up in grow bags. Most are dwarf and micros.
1010 is 10x10inches. Easy to tend for the first 6-7 weeks. I do keep them longer
in small cells than most do. But I have limited time and it works for me. I do give
a good chat when I check every morning,
, They seem patient until I can pot
up eventually.