Refresh my Memory on best fertilizer for seedlings?
 

I have been growing tomatoes for about 10 years, saving my seeds, etc. I have a city yard so can only grow 12-15 plants each summer (still I'm the crazy tomato lady around here because my tomatoes are mostly not red!) The last two years due to health and crazy life issues I grew fewer plant (two years of seedling failure meant I had to actually buy my plants - ugh), but we've rearranged the hard and are planning three new raised beds in a sunnier spot so I'm trying again. It feels like I don't remember anything that made me successful when I started out! please help!

I have to buy my seedling soil and fertilizer online this year, no stores are open but Walmart and I don't shop there.

The ONLY fertilizer I can find is Miracle Grow at a 18-18-21 or a generic 'garden food' at 12-12-12.

Living in Canada, I don't have anywhere to order the brands I used to buy and now seem to be impossible to find right now? I loved black gold starting soil and tomatotone fertlizier. Cant find them anywhere (without paying rediculous prices).
I'd love ideas of what I can do! I can buy Promix (BX or MP) in big bags, which is probably what I'll do for seed starting medium. I plant seeds starting next week for peppers, a couple weeks later for tomatoes.
Thanks!

Really depends on what you use for medium. Promix bx contains fertilizer already as do some others
For myself I use jiffy or similar sterile seedling mix and sometimes expandable pellets for certain things. They don’t contain fertilizer.
Then once growing I pot up at 2-4 leaf stage to something like promix HP which does not contain fertilizer.
If I used bx I would not add fertilizer at that point. But since I use HP I use
Balanced soluble 1/2 strength weekly until plant out and then switch to a 6-12-12 granular tomato fertilizer.
A million ways to do it, that’s what I do currently.
KarenO

I bought some Promix HP from Canadian Tire a while back. Ontario is in lockdown and I haven't been anywhere recently except to buy groceries, but I think they are doing curbside pickup.

I have some fish emulsion that I use (diluted) once a week, but I pot up into Promix for Herbs and Veggies which contains fertilizer. That is also available from Cdn Tire and Home Hardware.

Linda

I also use a very weak fish fert.