hi everyone iam looking for a small to medium size tree .
it will go in the front south facing garden i would like if possible to have a blossom tree
i'm dreaming of getting rid of inherited rhododendron one day that doesn't know if it's a shrub or tree... i'd have to go for a dwarf cherry , apple or almond , though it couldn't be much more than 8 feet for me, you may not have to go for dwarf
Hi Spencer - what time of year would you like your tree to flower?
There are some that flower in mild spells throughout the winter - those are Prunus subhirtella autumnalis http://www.telegraph.co.uk/gardening/3345615/Winter-beauty-Prunus-x-subhirtella-Autumnalis.html
or there are cherries (prunus) that are flowering about now and some that flower a bit later - lots here http://www.ornamental-trees.co.uk/ornamental-trees-c18/flowering-cherry-trees-prunus-trees-c34 Many of them also have fantastic autumn colour.
or you could go for the crab apples which flower a bit later in the spring http://www.telegraph.co.uk/gardening/3339094/On-the-spot-the-best-crab-apples.html and which have the advantage of being very good for bees and other pollinating insects, and the fruits can be used to make crab apple jelly, or can be left on the trees to feed the birds in the winter.
Or you could look at magnolias, which look fantastic about now, but which don't do much for the rest of the year.
I would go for an Ameleancher [ snowy Mesipilis ] Nice blossom followed by black berries, and, good autumn colour.
Amelanchier is ideal for what you want.
Am a growing fan of Prunus cerasifera 'Nigra'. Black trunk and branches with red leaves and pink flowers.
Snowy mespilus is lovely. Lots of good choices already mentioned but take a look at the weeping ornamental pear Pyrus salicifolius as well. I know you want flowers and they are insignificant but the foliage is beautiful - silvery grey.
Amelanchier is a lovely tree up to about 40ft (12m) in height. Delicate white spring flowers and lovely autumn leaf colour. Requires a lime-free, moist but well-drained soil. It does not thrive in very dry conditions and young plants in particular benefit from watering during dry spells.
Another tree worthy of consideration is the Cornus alternifolia (Pagoda dogwood). It has a lovely ornamental shape, a tiered effect created by its horizontal branching habit. In early summer it has creamy white flowers. Grows to a height of up to about 20ft (6m). Prefers a moist, free-draining acid soil in a partially shaded location so might not be suitable for you.