Hi Herbie , I think the bamboo you have is Phyllostachys Nigra. This is clump forming, so not invasive. Also makes a good pot specimen. Knock it out of the pot and check if pot bound. If so ,repot using a good loamy compost and water well. Top dress with some horticultural grit. In the summer months be careful not to let pot dry out . If you plant it in the garden incorporate some well rotted manure. Whatever you do, do it now before any frost or failing that wait until early spring. You will find when new shoots appear in spring, they will be green but will turn black. Cut out any weak canes every 2 - 3 years. Feed in spring with a general fertilizer. Bamboo is very hardy. Hope this helps. cheers skylight