I've inherited this plant from my mother and its been in the same pot of dirt for at least ten years. I haven't had any problems with it and it looks healthy to me so should I repot or just leave well enough alone? Does it need a bigger pot? What kind of soil? Any advice would be appreciated!
Hi, Cassandra. I JUST replied to a post about B recurvata over at Garden Web. I'll copy/paste what I left, with the hope you find it helpful. There is no rush to repot your plant, but I'd definitely put it on my list of things to do next summer after Memorial Day, when the timing better favors the plant. From the plant's perspective, there really are no plants that prefer to be grown with tight roots - they only tolerate the condition to varying degrees.
The copy/paste: The attributes that account for most of the ponytail's popularity are its ability to tolerate neglect and its ability to survive inadequacies much better than excesses. In the face of too little water, not enough nutrition, and cramped quarters for its roots, it remains stoic and ready to rebound when conditions improve. It doesn't tolerate excesses of water or fertilizers well, and responds to small pots by a growth rate that decreases as root congestion increases, as has already been noted, but tolerates tight roots much better than most other plants.
Growing it tight (keeping it root bound) restricts growth and vitality, but also reduces the probability of negative effects associated with over-potting - a plus for those using water-retentive soils. Fastest growth and best vitality can be had by siting in full sun and potting in a pot large enough for roots to have plenty of room to run, but that requires a soil that doesn't have a tendency to remain soggy to avoid that 'over-potting thing'.
If I wanted to grow this plant as close to its potential as possible, I'd grow it in a very large pot and a very fast (draining) soil.
Between now & then, you might want to learn about the difference between repotting and potting up. One practice ensures your plants will at least have the opportunity to grow to their potential, within the limiting effects of other cultural influences, and the other ensures it will not. This link is a good place to start: http://davesgarden.com/community/forums/t/1226030/ Your soil choice can also have a very significant impact on how close your plant CAN come to realizing its potential; so if you're interested in learning more about soils, the top sticky at the top of this forum has a lot of information that will help you gain a much better understanding of how to keep your plants' roots happy. Healthy roots are an absolute prerequisite to a healthy plant, the later being impossible w/o the former.