PlantFiles: Jerusalem Thorn, Palo Verde, Retama, Horse Bean, Lluvia de Oro
Parkinsonia aculeata

Very pretty in or out of bloom with bright green wispy foliage. The flowers are a bright yellow and add great color in the hottest part of summer. No or very little water once established in my area of the country. Yes its thorny, though the mature trunk is not and if limbed up and carefully placed its no big deal, mine is about 4' away from a path, and noone has gotten stuck yet. Messy? I don't think so but thats relative. I have people tell me their oaks, elms, whatever are messy all the time at work. Not used a lot in my area, even though it grows wild here, however I have people bring in pieces all of the time to identify because they find it so attractive.

Jerusalem Thorn, Palo Verde, Retama, Horse Bean, Lluvia de Oro Parkinsonia aculeata is native to Texas and other States.

Requires pruning like a lot of other trees.
I planted mine where it's not necessary to clean up pods or leaves.

A comparison between the flowers of five Palo Trees
--The Mexican Palo Verde (Parkinsonia aculeata), the upper petal starts out with red dots that eventually grow bigger and turn the entire top petal to red.
--The Palo Brea (Parkinsonia praecox), the upper petal has smaller & fewer red dots than the Mexican Palo Verde (P. aculeata) that don't grow bigger.
--The Blue Palo Verde (Parkinsonia florida), the upper petal is always a solid yellow just like the other four petals.
--The Little Leaf Palo Verde (parkinsonia microphylla), the upper petal is solid, all white, and the remaining petals are yellow.
--The Palo Brasil (Haematoxylum brasiletto), has flowers similar to Parkinsonia sp., and the top yellow petal has red dendritic streaks.

Fast growing tree, messy and do not recommended. Not appreciated here in Phoenix

In 1991 at a friend's newly purchased house, I rescued what I later learned was Jerusalem thorn. Some not so smart person had planted it a foot from the foundation, in full shade. It was a 6' stick of thorns, with a little ruff of leaves at the top! My friend is no gardener, so I took it home, CAREFULLY!

I planted it in full sun, on a mound of dirt. Well, 'dirt,' that's kindly put. Florida's native soil is generally nearly pure sand in many places. Nevertheless, this tough stick grew, and leafed, and flowered, and grew, and flowered again... I was very sad to leave it when we moved 40 miles away, but there was no way any of us was going to deal with moving this now very bonsai-ish 15' x 15' tree.

This is definitely a tree for a specific kind of site. You want to give it full sun, and really well drained not great soil. You want to give it room, for your own safety. Those thorns are serious. And you want to put it where it can be seen, because when it's in bloom, it is really beautiful. Down here it blooms twice a year -- rare in trees. I guess you don't want to put it near where you want neatness. I never noticed its messiness, but I put it where that didn't matter. That was just good luck, mind you. I knew nothing about it when I planted it other than it was going to be thorny.

This is one of the signature plants of the sonoran desert - Arizona, Mexico and small parts of California. It responds to moisture by growing a set of leaves when ever moisture levels are high enough. The green trunk and branches take care of photosynthesis the rest of the time! Lives alongside ocotillo, boojum trees, cholla cactus, etc, though maybe not quite as tough as they are.

I love the green trunk and the wispy leaves, but it drops them all year long! I am constantly cleaning up after this tree, bags and bags of trash!