The Boyce Thompson Arboretum was the biggest surprise of my Arizona trip last month. It was casually mentioned in some posts I found on various succulent forums online, but nobody I knew had ever been there. When planning my trip, I couldn’t decide for the longest time whether I should go out of my way to visit or skip it. But somehow it ended up on my itinerary, and I’m so happy it did. Maybe it was because my expectations were so vague, but the Boyce Thompson Arboretum blew me away, as you will be able to see in my three-part post. If you’re into succulents, this is a must-see destination. I look forward to visiting again and again since there are entire sections I had to skip altogether for lack of time.
The first thing you as you approach the entrance from the parking lot are plants for sale.
Plants for sale
Lots of them!
Plants for sale
If I’d had my own car with me, I would have loaded up.
Plants for sale
The selection was quite good…
Plants for sale
…and the prices were more than reasonable. But I was strong and resisted temptation.
Plants for sale
One of the first plant groupings I saw after I entered—WOW!
Located at the foot of Picketpost Mountain near the town of Superior, about an hour east of Phoenix, the Boyce Thompson Arboretum is Arizona’s oldest and largest botanical garden. It was established in 1924 by mine owner, financier and philanthropist William Boyce Thomson to pursue a variety of goals:
I have in mind far more than mere botanical propagation. I hope to benefit the State and the Southwest by the addition of new products. A plant collection will be assembled which will be of interest not only to the nature lover and the plant student, but which will stress the practical side, as well to see if we cannot make these mesas, hillsides, and canyons far more productive and of more benefit to mankind. We will bring together and study the plants of the desert countries, find out their uses, and make them available to the people. It is a big job, but we will build here the most beautiful, and at the same time the most useful garden of its kind in the world. 
In 1965 a cooperative agreement was signed with the University of Arizona to step up scientific research at the Arboretum, and in 1976 the Boyce Thompson Arboretum became an Arizona State Park. Over time, the size of the Arboretum increased from the original 400 acres to more than 1,000 acres at present. Only a fraction is developed for visitors, the rest is natural Sonoran desert.
Park map (copyright Arizona State Parks)
Right after entering the Arboretum I took the Curandero Trail. It highlights plants Sonoran desert people have been using medicinally for many centuries (“curandero” means “healer” in Spanish). In addition, you’ll find many succulents native to the Sonoran desert. I didn’t see any signs of irrigation equipment, so I assume plants make do with natural rainfall.
Agave ocahui var. longifolia
Agave chrysantha, native to Arizona
Tree beargrass (Nolina matapensis)
Feather tree (Lysiloma watsonii)
Agave shrevei ssp. shrevei
Agave toumeyana ssp. bella
The rare Boyce-Thompson hedgehog (Echinocereus boyce-thompsonii), named after William Boyce Thompson
View of Picketpost Mountain
Another mountain view through a ramada
Saguaro (Carnegiea gigantea) and Agave chrysoglossa
Agave murpheyi, another agave species native to Arizona
Back on the main trail, I didn’t know whether to look right or left, there was so much to see. Unlike the Curandero Trail, which was dedicated to plants native to the Sonoran desert, the plantings along the main trail come from dry areas all over the world.
Agave potatorum (front) and Agave ovatifolia (back)
Unidentified orange-flowering aloe
Ariocarpus retusus growing in a rock wall
Unlabeled dudleya, possibly Dudleya lanceolata
Clump of aloes next to a gnarled palo verde
Like the Arizona-Sonora Desert Museum, Tohono Chul Park and Tucson Botanical Gardens, the Boyce Thompson Arboretum has a Demonstration Garden that gives you “design and plant selection ideas for your home landscape.” 
Entrance to Demonstration Garden
The entrance is impressive enough, with towering eucalyptus trees, Yucca rostrata and massive Agave salmiana.
Pulque agave (Agave salmiana)
The foliage on this tree (liquidambar?) is so brilliant, it can be seen from a half a mile away!
Vignettes like the patio in the next few photos illustrate the kind of residential landscape you can create using desert plants.
Covered patio in the Demonstration Garden
Different view of this patio
Same unidentified aloe as shown earlier in this post
Desert Garden in the Demonstration Garden
Yucca elata and prickly pear
Another demonstration bed
Chairs inviting visitors to take a rest
This is the view you have sitting in these chairs
Two Agave ovatifolia
Beautiful plants wherever you look
The gray leaves of Texas ranger (Leucophyllum frutescens) contrasting nicely with the brilliant fall color
I ended up spending quite a bit of time in the Demonstration Garden, photographing the many different plants and admiring the views of Picketpost Mountain.
Another major section of the Boyce Thompson Arboretum is the Australian Desert. The eucalyptus grove is impressive, both in terms of the number of gum trees growing here and in terms of their size.
Interpretive sign for the Australian Desert section
Bridge over a dry creek bed
I love gum trees and ordinarily wouldn’t have been in such a hurry to walk through this area, but the Cactus and Succulent Garden was beckoning. As I was leaving the eucalyptus forest, I found myself at the edge of the “cultivated” part of the Arboretum. Here the views of Picketpost Mountain were simply amazing. I could have scrambled right up the mountain if I had wanted (and possessed the necessary physical fitness).
Saguaros growing on the slope of Picketpost Mountain
Picketpost Mountain silhouetted against the cloudy sky (no, I didn’t hang around until nighttime; I simply underexposed until I got the effect I wanted)
In the next part we will explore the Cactus and Succulent Garden at the Boyce Thompson Arboretum. You will be amazed.