How much to thin all depends on the type of plant. eg. most vegetables will be thinned to one per container IF you aren't planning to separate and transplant the extras as most do. But many flowers are grown in clumps so don't get thinned near as much.

So what plants specifically are we talking about?

Dave

Dave is right--Unless we know just what plants you have it's impossible to say. I grow my seed in containers and then transplant when they are bigger.

For instance I will put 3 Allyssum in one cell, but only 1 marigold, tomato or pepper. Also, which size pot I plant them in depends on the size of the plant or how big it will grow and how much root room it will need. I've been known to leave the occasional Petunias 2 to a pot.

So you see thinning or transplanting, it depends on a lot of things and it's impossible to give you a rule for everything.

Thanks for the feedback. All the plants are flowers-marigolds, celosia, balloon flowers, sweetpeas, hollyhocks, morning glories. Should I repot the thinned out seedlings in peat pellets in bigger jiffy pots before hardening off?

Thanks. I am new to growing from seed. When I was a kid, I just threw some seeds in the soil, but now that I do container gardening in a small apartment I don't have that luxury! LOL!

Your hollyhocks, sweet peas can go outside anytime now with reservations since they are already started.

Both don't mind cool temperatures and will withstand a light frost. I start them outside in a month or so before my last frost date, not inside.

With yours, Transplant them into individual pots and give them a week to settle in and then start hardening them off and then plant.

You can do the same with Morning Glories but They like it warmer and won't stand frost so don't plant outside yet. I usually start these outside too.

Then you will have room to separate the others. I wouldn't use peat pots. Do them in pots or paper cups with holes punched in the bottom and a good potting soil like pro mix. If you ever plant peat pots be sure to remove the pots or outer cover before you plant. Unlike they say the roots do not go through it unless it is sopping wet and it doesn't biodegrade in one season

Thank yo so much oilpaniter for your insssight and tips. zi didn't know that about the peat pots not biodegrading.