The Silk tree has a lot of sap coming out of the trunk.
It may have wetwood. This article may help:
http://msucares.com/pubs/infosheets/is1664.pdf
I bought a "hardy silk tree" from a catalog store this spring and it is growing, but I'm not sure what the bark of this tree should look like. For instance, at first I thought it had scale, but now I'm not so sure. This might be something that is normal for this tree. We live in the north midwest, so there are not any of these trees around that I know of. The "scale" I'm talking about are white bumps, but I did see these same 'bumps' on a hawthorne tree at a nursery not long ago. Any help here would be wonderful. Thank you.
Well, it certainly sounds like scale to me. This article should help with treating it: https://www.gardeningknowhow.com/plant-problems/pests/scale-bug-how-to-control-plant-scale.htm
We have found neem oil to be effective against these pests. Here is more information: https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm
I have it sitting in a glass of water and it is blooming indoors. Can I plant it in a barrel and leave outside, or do I need to keep it inside in a container and plant it in the spring? It is currently about 2 feet long. I live in Ocean City, Maryland.
It seems that you are in gardening zone 7b. Albizia is winter hardy in zones 6 and warmer, so you'll be able to plant it outside now if the barrel is large enough. In a small barrel, the roots will be more exposed to cold, so in that case it may need addition protection its first winter.
We planted above tree two years ago.. It has happily grown and has healthy foliage but no flowers..Should it have flowered by now. I have previously grown one in New Zealand which reached a wonderful height ,flowered, and that was nearly 30 years ago and its still there. We now live in Tasmania Hobart and hope this one will do the same
What are the temperatures like in your area? This link will give you a complete analysis of the tree: http://pfaf.org/user/Plant.aspx?LatinName=Albizia+julibrissin
We live in Wiltshire is it best to keep it inside over winter
Any good organic potting soil, amended with organic compost will be good!
Here are some articles that will help:
https://www.gardeningknowhow.com/ornamental/trees/mimosa/growing-silk-trees.htm
https://www.gardeningknowhow.com/ornamental/trees/tgen/growing-trees-in-containers.htm