which tree to buy

Now is a perfect time Ninah, I don't think it matters what tree as it will always be known as your doggies tree. The important thing is to get a tree that fits the space.

If you have a small garden, have a look at Prunus amonagowa, the flagpole cherry - takes up no space at all, really, because it grows straight up. Otherwise, small flowering trees - Malus, Cratagaeas, Laburnum, Rowan for a bit larger garden. Also have a look at Amelanchier lamarckii - it's not classed as a tree because it usually has more than one trunk, gets about 12 feet, blossom and fab autumn colour.

As Heron said size of your garden re size of tree.
Rowan trees such as Sorbus aucuparia Joseph Rock is suitable for most smaller gardens and provides all year interest. Prunus flowering cherries, Malus flowering Crab, or Laburnham.

Sorbus cashmiriana stays quite small, and can be pruned, pink tinted flowers in spring and large white berries in autumn that the birds don't seem to go for (at least in our garden) and has structural interest in winter [we have our outside christmas lights on ours].

A weeping cherry perhaps - Prunus subhirtella var. pendula.

As Heron says no mater what it will be your doggies tree

If can plnt away from hous, Prunus Kanzan is hard ot beet in Spring.
For summer try Hoheria sexstylosa inna warmspot with shelta in wintre.
Indigofera isa win too, but the choisest has ot be Aralia elata aureovariegata- the only decid tree to shed it branch -ita corker!!!!!
If you can wate, then the teirs of Cornus alternifolia argentia wil honor your pooch morso eech yr.
If you wate evn long, then the ultimat be Cornus contraversa variegata is outstandin.
Sumthin to sooth the soul be: plant an acorn sumweer. The Mighty Oak wil bea memry for centurees.

Plenty of ideas there for you Ninah, if you have another dog or if there could be young children around, Laburnam may pose a problem. I know someone who lost a dog after eating the fruit/seed

Malus are nice, you get the flowers in spring and fruit in autumn, a good all rounder, and there are many that are small trees

Some lovely ideas there. Another one,if you don't want anything too big is a weeping Japanese larch..ours is 6 yrs old and is only about 4 - 5 ft tall.

just a thaught if you empty the contents into the soil yoour plantinting the tree in and dig it in well at the bottem of the hole he will quite litteraly become part of the tree .you can put the urn in anyway or put it in the bottem.its just a thaught as thats whats happaning with my ashes.ive already planted the willow tree down bye the river ready for me

If you want laburnam, Heron's made a good point - just make sure you buy the variety L. watereri Vossi - this not only has the longest flowers, but also produces very, very few seeds compared to the other varieties.

Went for a walk in the park today and came across a Crataegus Prunifolia ( hawthorn) in fabulous autumn colours and smothered in red berries. In spring it has perfumed white blossom. It was so beautiful I am thinking of getting one .