S leucantha, right? They are pretty tolerant of most soils, but require good drainage to perform well. I would treat them the same way I would a shrub and repot (which includes root work and a change of soil) every year or every other year early in the spring. For this year, I'd cut off just the bottom of the root mass (if it has a concentration of roots at the bottom of the can), then cut some deep vertical slits in the root mass with a sharp utility knife, then pot up a size, using a soil similar to what it's in now. Next spring, I would bare-root, root-prune, and make sure it goes into a soil that won't limit its potential.

Can I ask what makes you want to grow this plant in a container?

Al

Here is a link that might be useful: Repotting tutorial

Yes, it's Salvia leucantha. I just found out that even though my plants are currently blooming Mexican sage is actually supposed to bloom only at the end of the summer. Disappointing.

I only have a container garden on my balcony. No yard. I was really attracted to the shape of the plant and the lavender flower color. The flowers are supposed to lure butterflies. I already have hummingbirds investigating it. If I keep it, it has to be in a container, so I don't want to give it a bad start with the wrong kind of soil mix. It was probably growing in the container that it came in for at least several months, so maybe it's okay.

But the soil does seem to be too heavy for a container, like it contains a lot of compost and sand. Am I missing that if you have a shrub in a container the soil mix should be heavier and slower to drain water than for something like a rose bush or perennial?

This post was edited by peterk312 on Mon, May 13, 13 at 14:03

Here's a photo of one of the plants.

{{gwi:28165}}

I trimmed only about 2 inches of roots from the bottom of the pot, and this was not even 1/3 of the total root mass. However, I've had this for only 3 days and the lower leaves are starting to yellow (the whole leaf, not just veins). I realize chlorosis can occur due to transplant shock, but like I say, I'm concerned the soil is not drying fast enough. Over-watering is the obvious cause of yellowing leaves, yes?

{{gwi:28166}}

Despite the soil being moist, this plant also appears to wilt in the late day sun. I don't know if that's normal for Mexican sage.

This post was edited by peterk312 on Tue, May 14, 13 at 10:03

I'd say that pot is more than 1 size too small. S. leucantha, unless you get the dwarf cultivar which this is obviously not, is a large and vigourous plant.

No, the pot is the same diameter and height as the pot it came in, and the plant was not root bound. The clay pot has a taper to it, reducing the total mass of soil mix to some extent. Moreover, the pot size is not why the plant's leaves are turning green. With roots slightly trimmed there is some room for growth this year.

--Again, the issue at hand is the soil mix type, which appears to be the compost-sand mix that I've always thought is too heavy for use in containers. The plant is blooming already, and it seems to have gotten either transplant shock or it's being over-watered because the heavy soil is not draining fast enough.

This post was edited by peterk312 on Tue, May 14, 13 at 13:55

The plant will tolerate 'very dry' much better than it will tolerate 'a little wet', so if you err, err on the dry side. If you're worried about the soil being water retentive, using a wick for drainage would be helpful, as would waiting until the pant feels completely dry if you stick a finger deep, or waiting until a wood dowel stuck deep in the pot comes out clean/dry before watering.

Al

Up until this week I have never bought a nursery grown plant in soil that did not drain well enough. From Lowes I bought a new Hydrangea "Forever & Ever Together". I have probably a hundred Hydrangea in pots. It is not possible to over water them in normal commercial used container mix. This new Hydrangea I added to my collection and in a few days it looked stressed.As with any stressed potted plant I removed the pot and found the terrible mix that looked like a mud ball. After removing much of the mix and repotting, I read the hang tag on the container. It said it would be necessary to water the plant every two weeks in most locations! From now on I will remove the pot from any purchased plants and see what mix they are planted in before the plant becomes stressed. Al

The Mexican sage was returned. I have never seen a plant diminish so quickly before.

Sorry you had to give up your Salvia. I never buy plants in full bloom, they just are not a good deal. Al