In Good Company: Companion Planting Display Garden (and Festa Botanica!) at the McConnell Arboretum and Gardens at Turtle Bay

Some things are just meant to go together: peanut butter and jelly; Acorus gramineus minimus ‘Aureus’ and Alchemilla mollis…..what??? Well, Grassy-leaved Sweet-Flag (Acorus gramineus minimus ‘Aureus’) a short, mounding, strappy leaved plant with a gorgeous lime-green color planted next to the ruffled-edged, saucer-shaped dark green leaves and the spikes of foamy-white flowers of Lady’s Mantle (Alchemilla mollis) – might just be a perfect plant combination. And finding new and great plant combinations is the goal of the new companion planting trial beds at the McConnell Arboretum and Gardens at Turtle Bay, says Lisa Endicott, Horticultural Manager at the gardens. Photo: One of the companion pairs intended by the McConnell Arboretum and Gardens is this between Carex barbarae (dun colored grassy plant at back) and Lysimachia c. ‘Atropurpurea’ (pale purple flower at bottom), however, plants (like people) have a way of forming their own companions no matter what the gardener intended. Here, the dark purple head of a Verbena adds a third and striking element to the combination.

Companion Planting as a concept is as old as mother nature – who routinely puts plants together that work well together and for the most part, they look good together, too. Companion Planting as handled by mortal gardeners is a technique used to see which plants that you might not expect to see together actually make great companions anyway. The success of their companionship is based on a variety of criteria: (Photo: Rosemary planted against a backdrop of the dramatic Muhlenbergia lindheimeri.

1. Do they look good together in terms of contrasting or complementing in an interesting and appealing way? Like the foliage contrast described above might do;

2. Do they form some kind of beneficial/symbiotic relationship with one another? For instance, it is long believed that marigolds planted around the edges of your vegetable beds will help to deter pests from your vegetables. As the complex life of soil and its world of micro-organisms and micro-nutrients is better understood, it is clear that some plants form beneficial nutrient-providing relationships with one another. This is the basis behind planting beans or peas in the in the same place you had your tomatoes planted – because tomato plants require large amounts of nitrogen from the soil, and peas and beans re-fix nitrogen back into the soil as part of their life-cycle. So they make perfect follow-up companions.

3. Do they have similar requirements in terms of water/soil/exposure/food even though they might originate from different parts of the planet?

These are some of the issues that Lisa and her staff wanted to consider when they began planning and installing their Perennial Companions Display Garden trial beds in 2007. “It’s so difficult to look at a perennial plant in a pot at a nursery and be able to visualize what it will like when it grows up in the garden, and even more difficult to visualize what it might look like next to another plant – especially if you’ve never heard of either one of them,” Lisa said as we walked the Companion Planting beds last fall. “We wanted a section of the garden devoted to experimenting – so we as the gardeners could try new combinations and so that visitors could see the results along with us. We hope, we will all get new ideas and information from the trials!” BEST PART OF ALL? these beds are not inside the paid portion of the gardens – they are open to the public at all hours of the day – just across the Sundial Bridge from the Exploration Park part of Turtle Bay and on your left as you head to enter the main portion of the gardens. The Perennial Companion Display Garden beds are tucked in behind a hedge of manzanita – and a portion of the beds are beneath a small shade structure, so that the gardeners could experiment with shade-loving plants (and people), too. Photo: The tall blue flowers of Penstemon heterophyllus interplay nicely against the silvery-yellow of Artemisia californica.

This year-round easy access to the display beds means that you can always just pop in and see what’s happening – see how the companions are getting along, how they look in different seasons, how the gardeners are caring for the beds so that you know when they cutback, when they mulch, when they feed, and water. All told, the Perennial Companions Display Garden now comprises 15 long rectangular beds, laid out and labeled in sub-squares and rectangles running down the length of the bed. Many of the combinations that the Garden staff is looking at involve foliage combinations and/or foliage/flower combinations; still other combinations are California natives and Mediterranean climate natives – these last two of course being the signature strengths of the McConnell Arboretum and Botanical Gardens. “Grasses are particularly fun to play with out here,” says Lisa, “in part, because they can look so terrible in their pots: stunted, sometimes squashed down or root-bound in their pots. But get them planted up and have another plant grow up and maybe even flower into them and – Wow – you have a gorgeous combination!’ Photo: when working out interesting combinations in your garden, think about seasonal issues as well. Here burnt-red seed heads of an Eriogonum pop out behind the fresh green foliage of an Arctostaphylos in winter.

About half of the Perennial Companion Display Garden beds were planted in August of 2007 and the remainder of them planted in June and July of 2008. “This spring and summer, you should really see these beds take off and start to look like something – and we are collecting data about the plants the whole time,” Lisa explained to me “We hope to have the information available on-line as we go along. Once we think we have a good sense of a combination, we will also change things up and try new combinations. It’s an on-going process – like all gardening!” Photo: Contrasting forms and colors often make for good companions in terms of aesthetics.

This weekend – April 24 and 25 – is a perfect time to go over to the gardens and take a peek at the new Perennial Companion Display Garden, because Festa Botanica! -the McConnell Arboretum and Botanical Gardens 1st Annual Spring Garden Festival and Plant Sale – will also be under way. The Turtle Bay members-only party and presale is Friday April 24th 4 – 8 pm. (Memberships are available at the door). Saturday, the event runs 9 -3. Join the fun – go check it out – you’ll be in good company. Photo: A border along the public walkway before you reach the new Companion Planting Display beds shows how accomplished the McConnell Arboretum gardeners are with plant combinations. Here California Fuschia blooms in front of a tall-form Sedum, which is backed by an silvery Artemisia – the overall impression is like a tapestry. It is also regionally appropriate, heat and drought tolerant.

Interested in some additional reading on Companion Planting? Check out these books: Perennial Companions: 100 dazzling Plant Combinations for Every Season, Tom Fischer, Timber Press 2008 Designer Plant Combinations, Scott Calhoun; Storey Publishing, 2008 Great Garden Companions: A Companion Planting System for a Beautiful, Chemical-Free Vegetable Garden, Sally Jean Cunningham; Rodale Press, 2000 Carrots love Tomatos: secrets of companion planting for successful gardening, Louise Riotte; Storey Publishing, 2nd Ed 1998 Roses love Garlic: companion planting and other secrets of flowers, Louise Riotte; Storey Publishing, 2nd Ed 1998 Rodales Successful Organic Gardening Companion Planting, Susan McClure & Sally Roth; Rodale Press, 1994 Good Neighbors: companion planting for gardeners, Anna Carr; Rodale Press 1985

In a North State Garden is a radio- and web-based outreach program of the Gateway Science Museum – Exploring the Natural History of the North State, based in Chico, CA. In a North State Garden celebrates the art, craft and science of home gardening in California’s North State region, and is conceived, written, photographed and hosted by Jennifer Jewell – all rights reserved In A North State Garden airs on Northstate Public Radio KCHO/KFPR radio, Saturday mornings at 7:34 AM Pacific time and Sunday morning at 8:34 AM Pacific time. Podcasts of past shows are available here.

Jennifer Jewell

In a North State Garden is a bi-weekly North State Public Radio and web-based program celebrating the art, craft and science of home gardening in Northern California and made possible in part by the Gateway Science Museum - Exploring the Natural History of the North State and on the campus of CSU, Chico. In a North State Garden is conceived, written, photographed and hosted by Jennifer Jewell - all rights reserved In a North State Garden airs on Northstate Public Radio Saturday morning at 7:34 AM Pacific time and Sunday morning at 8:34 AM Pacific time, two times a month.