Plants are a huge and fascinating group to study. Unlike animals they tend to be pretty much stationary and hence are easy to get a good look at and get to know in detail. They are more predictable in their occurrence and distribution than animals and hence easier to find. However they can still present considerable challenges to the serious plant hunter and provide great rewards.
For W2WW pages listing British vascular (i.e. flowering) plants see below:
The following table has been taken from English Nature's web site and gives approximate numbers for plant species found in Britain. Fungi are also shown below.