When rebuilding roots, especially in a hot South Texas, I'd avoid full sun on Echeveria. Morning sun, bright filtered sun, in the shadow of a taller plant -- that's how I'd do it. Especially in containers, plants which live in full sun in habitat sometimes lose their roots when we grow them in containers in full sun because the pot and soil get too hot... root die-back combined with moisture is often the cause of root rot -- not always overwatering, which is the most popular diagnosis. But also, I find these soft Mexico Crassulaceae slow down a lot when temperatures exceed 90 degrees. You have to pay attention: the plant can't take up as much water if the roots have already died back or when the plants have stopped (and excess water will cause problems), but if the roots are still healthy, you don't want their soil to get bone dry, which will cause the roots to die back.

Here in Southern Californa 10a with temps in the 90s today, I do have a lot of echeveria in individual pots, but honestly my best performers are in big, community pots (in one case, around the base of a Ficus benjamina) where the roots aren't subject to as much temperature and moisture fluctuation and they have room to grow.

what if you have a plant with no roots at all is there no hopes?

Sure there's hope. That's part of what makes cactus and succulents fun. I have lost hope so many times, only to later find a plant has "recovered from the dead". But if the roots are completely gone, I would consider transplanting. The soil in that pot may have broken down or become overrun with pathogens.

Sterilize a sharp knife or razor with a bleach solution (1 part household bleach to 9 or 10 parts water) or any premixed, bleach-based household cleaner. De-pot the plant and remove any broken down bits of soil or dead roots. Cut away any blackened, softened parts of stem. Leave the healthy part of the plant to rest for several days in a temperate, dry area to allow the cut areas of stem or thick roots to callus. (A shelf in your house or garage is good.) Light or dark doesn't really matter at this point.

Plant the callused stem in a fresh or sterilized pot. Choose a pot with approximately 1 or 2 inches on all sides of the stem you're trying to root. Much more than that, and you're inviting fungus to take hold before your plant can establish its roots in that pot.

Now, some folks will tell you not to "water in" this cutting at this stage. In my climate, with my sharp-draining 80% grit and pumice or perlite, it works better if I "water in" at this point, especially since we already allowed the stem to callus.

Either way, the darkness (and to lesser extent, humidity) of the soil next to the stem will encourage the stem to send out roots. The callus will help protect your stem from opportunistic pathogens entering from the soil, and may be the source of new root growth.

The basic principle is that you want the soil right around the stem to be humid but not moist. Heavy dampness or (worse!) wetness will promote fungus in the soil before your plant has roots in the soil to compete.

Don't put this in full sun! A bright, shady porch or maybe east-facing (morning sun) but shade or heavily filtered, dappled light after that -- even full shade should work okay, but I like to give my plants SOME ongoing energy in the form of filtered light.

In a few weeks of occasional spritzing, your plant should start to have roots in the soil and you can start watering normally -- carefully at first, and with more confidence once it's clear the plant is taking up the water you give it.

By "occasional spritzing" I'm talking about keeping the layer of soil next to the stem slightly humid. So I spray or drip a little water on the soil near the stem to accomplish that. I don't mean spritzing the foliage, though a little splash isn't a problem.

As Jeff cactusmcharris says, "Practice benign neglect."

Hi DC,
How would I treat a plant that is inside and always has been, to re root her?

I have one that was a gift, and I'm afraid I was over protective, and now the stem at the base seems to have shrunk just above the potting mix.

You mentioned putting them in the shade, or bright filtered light, I have an east window, or south, or a table in the middle of the room for plants.

I really don't want to put her outside.

I hope I can save it, it is dear to me for alot of reasons.

I think I was so afraid of messing it up, that I did in the end. I'm thinking I under watered at some point.

Thanks,
JoJo

I have done that so often! Read someone's culture recommendations and underwatered my plants. Luckily they're succulents and most of them survived.

What kind of plant? A lot of Crassulaceae and other plants in our hobby are vigorous enough to regrow the fine root hairs they need without needing to change the soil, unless the root ball is sick or the soil is old and broken down.

Even without knowing what your plant is, if the sunlight is direct, I'd say east to be safe. I have tons of plants which can't deal with most direct sun, but even they love morning sun. And any window is fine if the sunlight is filtered or indirect.

Honestly, for this process, middle of the room should root okay, too. I've even rooted plants in a closet. That's too dark for the plant to actively produce much energy, so it would have to grow the roots with stored energy. But our succulents store a lot of energy. But again -- luckily -- our plants are succulents and they store a lot of energy.