There are no true trees that stay that small.

That said, there are certainly shrubs at your required height that you can kind of prune into tree-like forms:

Dwarf oleander
Dwarf myrtle
Hawthorn
Tea Tree (Leptospermum scoparium -- underutilized and very stately in my opinion)

Texas Mountain Laurel is slow growing so you could keep that under your height restriction for a while.

By patio does that mean in a container?

Not necessarily, although they'll likely work in a big container (for a while). "Patio trees" are smallish (usually around 15 ft tall at maturity), well behaved and not-too-messy, which makes them ideal for small yards.

This post was edited by Oxboy555 on Fri, Sep 5, 14 at 1:15

I mean does the OP required to use a container? Like does this have to be actually on a patio or next to a patio?

uhm . . . what about ficus benjamina ? ? ? That is "not a tree" ? ? ? They are planted ALL OVER as "patio trees" from my experience

We used to have about 8 of them. . . braided trunks - never loses leaves unless you have a major frost!

My ficus benjamina would lose leaves if I just looked at it cross-eyed.

They (ficus benjamina) will lose leaves if you adjust them in the slightest due to light changes BUT they will regrow pretty quickly if this happens. Also, extreme cold will cause frost damage and I've had leaf loss when I missed a watering cycle during the hot months too . . . but it has been a pretty great tree nonetheless!