Botanical Tour: Leaning Pine Arboretum

Nestled in the hills above the Environmental Horticulture Science Unit at the north end of the Cal Poly campus in San Luis Obispo, a stunning five-acre display garden secretly sits, tucked away from student traffic and hidden from view.

 Welcome to Leaning Pine Arboretum

Welcome to Leaning Pine Arboretum

I visited Leaning Pine Arboretum last week, for the first time in years, and an immediate sense of nostalgia arrived just as I did. After endless hours spent wandering through its winding pathways, welcomed by weeping boughs and mesmerized by back-lit blooms, this magnificent place holds a truly special place in my heart.

 The Dwarf & Unusual Conifer Garden

The Dwarf & Unusual Conifer Garden

 Grasses blooming in winter, illuminated by sunlight

Grasses blooming in winter, illuminated by sunlight

 Aloe plicatilis in the South African Garden

Aloe plicatilis in the South African Garden

Over fifty years ago, Leaning Pine Arboretum was established as a two-acre collection of various tree species, which was developed into the existing five-acre botanical garden by long-time arboretum director Tom Eltzroth. He contributed his extensive horticultural knowledge with enthusiasm, led fundraising efforts, created information tools including signage and a website, and implemented sustainable gardening methods. After over forty years with Cal Poly and eighteen years as the director, Eltzroth retired in 2008, and the arboretum is now managed by (my former arboriculture teacher) Chris Wassenberg.

 A combination of plant forms, textures and hues

A combination of plant forms, textures and hues

 Back-lit Acacia in the Australian Garden

Back-lit Acacia in the Australian Garden

 Leucospermum in the South African Garden

Leucospermum in the South African Garden

Leaning Pine Arboretum is constantly putting on an ever-changing show of foliage and inflorescence, attracting beneficial and pollinating insects, wildlife, and people alike. The garden contains hundreds of plant and tree species, mainly natives to the five Mediterranean climate regions of the world, which are well-suited for our California landscapes. Plant collections from Australia, South Africa, Chile, the Mediterranean, and California are all featured in the arboretum, alongside a New Zealand Garden, Formal Garden, Palm & Aloe Garden, Dwarf & Unusual Conifer Garden, and a Primitive Garden.

 Muhlenbergia rigens provides bio-filtration and stabilization for a swale in the California Garden, while Bishops Peak overlooks

Muhlenbergia rigens provides bio-filtration and stabilization for a swale in the California Garden, while Bishops Peak overlooks

 Cycads in the Primitive Garden

Cycads in the Primitive Garden

 Aloes blooming among other succulents and palms

Aloes blooming among other succulents and palms

Since its inception, the arboretum has been used as a living laboratory; horticulture, botany, forestry, and entomology classes all utilize the garden as a hands-on outdoor classroom, embracing the Cal Poly motto, Learn by Doing. During my time as a horticulture student at Cal Poly, Leaning Pine Arboretum was where I memorized a never-ending list of Latin plant names and learned how to properly climb a tree with gear; where I sucked up tiny insects in an aspirator to identify for my entomology collection and sharpened my chainsaw skills; where the Adirondack chair I built in my landscape construction class was placed, and still sits to this day (eight years later), a bit worn and weathered but steadfastly providing a place for visitors to rest and become enveloped and enchanted by the botanical world around them.

 Agave blues in the Palm & Aloe Garden

Agave blues in the Palm & Aloe Garden

 A succulent-surrounded seating area

A succulent-surrounded seating area

 The olive grove anchors the Mediterranean Garden.

The olive grove anchors the Mediterranean Garden.

 The pathway winding through the California Garden

The pathway winding through the California Garden

 Agaves in the California Garden

Agaves in the California Garden

Besides functioning as a learning space for students, the arboretum is a valuable resource for community education and recreation. Self-guided tours by brochure or by cell phone are available, and organizations can arrange for a guided tour by an arboretum staff member. For those looking for a more informal experience with the garden, they can simply meander along the blue-grey decomposed granite walkway that loops through the property, connecting the plant collections and gathering spaces. There are signs positioned to direct visitors through the arboretum, and plant varieties are individually labeled in each section. 

 Signs lead the way

Signs lead the way

 The main pathway, flanked by California and Mediterranean natives 

The main pathway, flanked by California and Mediterranean natives 

 The gazebo and lawn area, just beyond the California Collection

The gazebo and lawn area, just beyond the California Collection

Seating areas are scattered throughout the five acres, including a semi-circle stone bench in the California Garden that wraps around a fire pit and boasts breathtaking views of Bishops Peak and the surrounding hills. A gazebo abuts the picnic-perfect lawn area, and a built-in BBQ can be found right inside the arboretum entry. Leaning Pine Arboretum is an ideal place for a peaceful stroll in solitude or an afternoon nap in the sun, photographing flora and fauna, a weekend outing with friends and family, finding inspiration for your own space, and so much more. It's open to the public year-round and fee-free, so there's no excuse not to take advantage of this local beauty!

 The South African Garden, covered with Crocosmia

The South African Garden, covered with Crocosmia

 A honeybee visits a Hardenbergia blossom in the Australian Garden

A honeybee visits a Hardenbergia blossom in the Australian Garden

 Glowing Leucadendron bracts, from South Africa

Glowing Leucadendron bracts, from South Africa

Check out http://www.leaningpinearboretum.calpoly.edu/ for more information on the plant collections, horticultural practices used in the garden, and visiting the arboretum.

 One of my absolute favorites, this California-native Manzanita is vibrant in the January sunlight

One of my absolute favorites, this California-native Manzanita is vibrant in the January sunlight