Hi everyone! This sub has been incredibly helpful as I am growing tomatoes for the 1st time ever, and decided to try from seed. I planted 1 week ago in a 72 cell tray in a seed starting mix, 2 (some have 3) seeds in each cell, used a humidity dome and heating mat, and have been bottom watering. The sprouts started to pop on Friday morning so less than 4 days after planting. I removed the heat mat and humidity dome once they started to sprout and put the growing lights on them. I have been doing 16 hours on, 8 hours off for the lights.
When should I start thinning these out and getting rid of some of them? Realistically I probably will only want to keep about 10 plants, 5 of each as I planted both cherry and romas.
I plan to pot up to 4" nursery pots once they have 2 sets of true leaves, is that a good plan? Any recommendations on a potting mix to use or just any decent looking potting mix for vegetables that I can find at Menards/Home Depot etc?
When should I start to fertilize? Any recommendations of a brand and/or type of fertilizer?
I am in Wisconsin so these won't be ready to go outside until about Mid-May. I plan to keep two plants for myself of each type in a 10-15 gallon pot each with tomato cage. I plan to harden them for a couple weeks before transplanting to outside.
Anything I am missing?
Thank you so much for any advice you can provide! I am already having a lot of fun with this and trying not to overthink too much but also want to set myself up for success.
by Bshoener1
6 Comments
Give them time. Water every day at this stage. Fan can’t hurt.
72 cell! You have a lot.
If it were me, I’d start by thinning within the cells right now. Look for the best seedling (thick stem, but leaves) and snip the other two (don’t pull, u can damage the roots of the one you want to keep).
After their first true leaves fully develop (it’s started to try to grow taller and produce the second set of true leaves), consider potting up your best looking seedlings. You can pot up a few extra as backups. The rest you can give away or compost.
At that stage, you can also start giving fertilizer VERY LIGHTLY. I’m just giving a diluted miracle grow (1tsp/gallon) cuz it kinda works for everything and i want the extra nitrogen early for more leafy growth.
You could get some slow release tomato fertilizer. Any brand is good I suppose. Check what your local nurseries have. I heard fox farms is good too
Generally you can use diluted fertilizer when you pot up at 2-3rd leaves stage. Everyone is a little different on timing for transplanting. The seedlings appear to be stretching for light, you may try lowering your lights a bit. Be careful because too close can cause burning. At this stage I have oscillating fans on to circulate air, it will strengthen the stems and help prevent fungal issues like damping off. Bottom watering is good, continue with that. Thinning can happen now but the roots are very delicate. If you have the small snips,
I’ve seen recommendations to use those to snip off at soil level. I normally separate at the time I transplant. When you transplant, hold the seedlings by the leaves not the stem. Leaves will grow back, the stem is sensitive and can bruise easily.
Good luck! Love seeing people giving seed starting a go!
Yes thin them now to get one per cell, yea a couple of true leaves is usually a good time to transplant, I do it around there when the roots look right. I up pot them into a cheap potting mix and I just pick out the big chunks, no big deal. If you’re worried just get a “container mix” and it will be fine out of the gate.
Fertilize after you’re getting a true leaf. I just use 1/4 tsp of miracle grow (20-20-20) per gallon of water because I have it and use it with chemigation. I sometimes use Alaskan fish, but I don’t over think it.
The rest of your plans, like light and timing all look fine to me, pretty similar to my own honestly. Hardening off is more about the sun exposure for me as a northern guy too, so don’t sunburn them out of the gate when you get to that phase.
Well done, the hardest part is done.
Buy more of these lights…..then burn them so other people cannot buy them.
Seriously though, get more, stronger lights. Soon!!
They aren’t getting enough light. They shouldn’t be that tall and thin.