It is a Parthens red.

This year, I planted in large black plastic containers with a 50%/50% mix of MG potting soil and compost. They thrived in that. I added organic matter periodically (coffee grinds, coco bean mulch, etc.) and fertilized once a month. I also interplanted with Lysmachia ('Creeping Jenny' & 'Jungle Green') to cover the black pots and act as a natural mulch. Seemed to help retain the water quite a bit.

If you mean Fouquieria splendens, I have two, one about 3-1/2 feet tall with ten or so stems, the other a single stem about a foot tall (and a few seedlings). I was told that these were delicate, and would surely die if I watered them outside the Arizona "monsoon" period (July-Aug), but I've just left them outside on the patio and after two years in the Virginia sun, they're doing fine. The larger one even lived through being buried under snow for close to a week. My conclusion is that they're fairly hardy, and probably any reasonable succulent soil would be fine -- mine are in my standard mix of 1/3 washed Napa 8822 and 2/3 Scotts Topsoil. This is what the seedlings look like. For the first few years, they grow very slowly...then get a growth spurt and grow close to an inch a year! -R

First, conifers like pines and cedars dropping needles does not make soil acidic. That is due primarily to the underlying mineral component of the soil and the amount of rainfall the area receives. Heavy rainfall areas tend towards acidic soil. Since the vast majority of plants prefer acid soil anyway, you are probably good to go. With lots of the trees in the area, your primary concern is going to be root competition and lack of soil moisture and a sparsity of nutrients as a result. Big trees have big, aggressive root systems that hog all the goodies. Plants you select to go in this area should be drought tolerant and not have a lot of other demands regarding nutrient issues. Even then you will need to baby them for a couple of seasons with water and fertilizer until they become established. I'll second the Beth Chatto rcommendation. And I'd add The Complete Shade Garden, by George Schenk. Both should have numerous suggestion of plants recommended for dry shade.