I would make sure they are moist but then water after you transplant. Take the peat pots off, they can block root growth. Prune off the bottom set of leaves and bury them right up to the next set of leaves. If the plants are long, lay the stem down in a small trench and bury it. I would also put some kind of mulch around them to keep splashing dirt off when it rains. For peppers you don't bury the stem.

I pour a minimum of two gallons of water on the tomato plant immediately after I transplant it, but I live in southern California where the soil will always be dry unless you water it because it doesn't rain here except in the winter. If you water before you transplant and have clay soil like I have you will just make it very messy to dig in it.

"Also they have been hardened off, so can I just put them in full sun or do they still need to be gradually accustomed to outdoor weather? "

If your tomatoes have been properly hardened off, they will not need to become accustomed to outdoor weather, they should already be used to it. If they have not been outside in the weather, they aren't hardened off because that is part of the process.

But if they have been outdoors and properly hardened off there, yes, you can plant them in full sun.

Many people cross cut the bottom of peat pots so that the plants don't have to work so hard to get their roots into native soil or whatever they are planted in. Others take them off, some slash the sides and bottoms.

As for fertilizing when planting, that is a pretty good time to do it. If it isn't an organic (slow to break down and release nutrients) be careful to keep it away from the stems and roots by at least 5-6" so that you don't get fertilizer burn.

Betsy

Here is a link that might be useful: Hardening Off and Physiological Changes

Well I mean which would be better for the plant with the peat pot, removing it entirely or just cutting off the bottom part of it?

Also I was told that the more you bury the stems, the stronger the plant will be?

That I should bury the plant up to the first set of leaves (with tomatoes; I also will be transplanting tomatillo plants, so would this rule apply to them to?)

A really stupid question but where is the first set of leaves? How far up the plant do they go? When it says the first set of the leaves, is it referring to the cotelydons (baby leaves) or the first set of true leaves?

Also this is off topic but on the bottom leaf, there are some pale brown spots. The leaf is kind of yellowish-green. The rest of the plant looks healthy. Is this something to be concerned about? I don't know what the cause of it is really.

Well I mean which would be better for the plant with the peat pot, removing it entirely or just cutting off the bottom part of it?

Remove it.

Also I was told that the more you bury the stems, the stronger the plant will be?

True. Roots develop all along the buried part of the stem. Try to bury at least 1/2 the stem but since you are using containers that may not be possible.

That I should bury the plant up to the first set of leaves (with tomatoes; I also will be transplanting tomatillo plants, so would this rule apply to them to?)

Yes.

where is the first set of leaves? How far up the plant do they go?

It is obvious where the first set of leaves is and no, the cotyledons are not leaves.

there are some pale brown spots. The leaf is kind of yellowish-green.

Just remove it before planting it.

Dave

"Well I mean which would be better for the plant with the peat pot, removing it entirely or just cutting off the bottom part of it?"

"Remove it."

I've seen a lot of tomatoes in peat pots, and their roots had seriously grown through the pot and if that is the case with yours, I'd be hesitant about ripping off all those roots, as that would probably really increase the transplant stress.

If the roots have not grown through, remove the pot. If they have grown through, do what you can to allow others to grow through in a natural environment. (For some reason roots will grow through the pot easily until they are planted into their final home, then it is like it becomes a brick wall. Perhaps because the perched water level becomes much lower than the bottom of the pot?)

I'm just sayin'.

Betsy

Sorry to disagree Bets but there really is no benefit whatsoever to leaving the peat pots in place and many well documented benefits to removing them. Removing them is the #1 best way to avoid stressed/stunted plants.

Soak the peat pot well first and it will tear off easily. Any damage done to the roots is minimal and actually stimulates new root development just as cutting/dividing the root ball of any root bound plant will do.

Dave

So if you want to compare, after you remove the peat pot, plant it and then check on it later in the season. End of season would be best but don't forget. I don't use peat pots any more.

Leaving peat pots on does stifle the root/plant development.

This is a helpful string. I am planting tomatillos for the first time this year and have wondered how much to treat them like tomato plants. What if the tomatillo seedling has flowers and buds. Should I pinch them off prior to transplanting so that the plant puts it's energy into root development?

I would pinch them off, yes.