Permaculture

Nature is a permacultural landscape. Annual plants occur everywhere in nature. To exclude annual plants from a permacultural landscape is purely ideological and has no basis in ecology. However, the contemporary movement toward sustainable food production is an absolute good, and the sometimes anti-annual paradigm of permaculture is at the heart of that movement. We should all aspire to include a diverse selection of perennial and annual edibles in our gardens, and to procure whatever we may need to manage those gardens from the gardens themselves. It is economically and ecologically prudent to do so.

Perennial Edibles

You’re already familiar with them. If not your mother, then probably your grandmother had asparagus and rhubarb in her garden. When I was growing up in rural Iowa, old abandoned homesteads were easily identified by rows of these, as well as irises and peonies. They were the backbones of a garden that produced most of the food and flowers a family could need. They tolerate frigid winters and extreme heat. They thrive on neglect. They are as old as the trees. They are models of what we want to achieve in the modern permacultural landscape.

Rhubarb (Rheum x cultorum) and asparagus (Asparagus officinalis) can both be grown from seed. Seed-grown rhubarb can be harvested the second year, and seed-grown asparagus the third year. Strawberries can also be grown from seed, and the tiny Alpine varieties (Fragaria vesca) are everbearing and will produce fruit the first year. Mara des Bois are the tastiest of hybrid strawberries. They are also everbearing and produce a prodigious number of runners, making them one of the more reliably perennial strawberry plants available. Several species of hardy and long-lived Rubus, Ribes and Sambucus can be grown successfully from seed.

Alliums are some of the most delicious, nutritious, and reliable edible perennials. Welsh onions (A. fistulosum), Chives (A. schoenoprasum), Garlic Chives (A. tuberosum), Nodding Onions (A. cernuum), Alpine Leeks (A. victorialis), Egyptian Walking Onions (A. x proliferum), and Potato Onions (A. cepa var. aggregatum) are just a few Alliums that are hardy to at least zone 5. Some Alliums, like Garlic (A. sativum and A. ophioscorodon) and Griselle Shallots (A. oschaninii) are best harvested in the summer and replanted in the fall, but also qualify as perennial. It should also be noted that Garlic is indispensable as a medicinal and makes an effective pest repellent.

True perennial salad greens worthy of a place in the garden are hard to come by: Salad Burnet (Sanguisorba minor) emerges in very early spring, stays fairly compact and attractive, and tastes of cucumber. Lovage (Levisticum officinale) presents with tender, aromatic greens in early spring before becoming potentially obtrusive in size. Its stems can be used in place of celery, and its medicinal roots can be also be candied. Several species of Rumex qualify: Patience Sorrel (R. patienta) is a mildly flavored and incredibly prolific true perennial salad green, and short-statured Buckler Sorrel (R. scutatus) features a incredibly unique shield-shaped leaf and a clean bright lemon flavor that is suitable for salads, sauces and soda. Broadleaf Sorrel (R. acetosa) is the species most commonly found in American gardens, likely by virtue of its easy culture rather than charm. Bloody Dock (R. sanguineus) is more ornamental than edible. Be advised that all Rumex species contain oxalic acid, and their use may be best limited to very early spring, when little else is available in the garden. 

Some perennial greens are well worth cultivating but have no place in the garden proper: Mitsuba (Cryptotaenia japonica) and Claytonia (Montia perfoliata) should be sown in moist soil in part shade, and where their rather invasive habit will not overwhelm other cultivated species. In Japan, Mitsuba is harvested as an annual, roots and all.

Self-sowing annuals and biennials can function as perennials in a permacultural landscape: 

Mâche (Valerianella locusta), Shallot Cress (Lepidium campestre var. mahantongo), and Dutch Broadleaf Cress (Lepidium sativum), are especially delicious self-sowing salad greens. They are at their best in the cool of autumn and can frequently be harvested through the winter. They are fairly inedible or dormant in the summer months, and are suitable companions for strawberries and chives. Nasturtiums (Tropaeolum majus) will sometimes self-sow under a canopy of fruit trees, providing delicious leaves and flowers for salad throughout the summer and autumn.

Growing a single variety of many Solanum and Physalis species will allow them to self-sow quite true from year to year. Be sure to thin plants early! Currant Tomatoes (Solanum pimpinellifolium), Tomatillos (Physalis ixocarpa), and Ground Cherries (Physalis pruinosa) are excellent candidates for the permacultural landcape as they self-sow prodigiously and require zero maintenance once established (although currant tomatoes do benefit from being trellised). Keep in mind that currant tomatoes should be somewhat isolated from garden tomatoes (Solanum lycopersicum), with whom they will easily cross.

Salsify (both Tragopogon porrifolius and Scorzonera hispanica) are hardy biennial roots whose spring growth can be cultivated as greens or an asparagus-like vegetable in their second year, and their very ornamental edible flowers (whose unopened buds are a delicacy) produce seeds that can be allowed to sow themselves willy-nilly or collected and sown where you'd prefer they grow. Roots can be harvested anytime after their first frost, through the winter, and even in their second year after flowering. Sow seeds again in the second year to have a consistent supply of roots and shoots for years to come.

Another biennial root vegetable, Parsley Root (Petroselinum crispum var. tuberosum), sometimes known as “Hamburg Rooted Parsley", produces both an edible root and delicious, snow-impervious parsley, and will self-sow to the point that you need never be without roots or fresh parsley if you remember to start new seedlings the second year. Be sure to thin transplants and self-sown seedlings to at least 8" to allow for the development of large, tasty, aromatic roots, which can be harvested well into the winter, like parsnips.

There are a wide variety of perennial edibles, barely differing from their wild counterparts, that may be incorporated into a permacultural landscape. They sometimes require very specific culture. They can often be very long lived. Among these are Skirret, Sea Kale, Oyster Plant, Oca, Arrowhead, Alexanders, Samphire, Quamash, Crosnes, and Scotch Lovage.

Plants that Nourish Plants

The real secret of sustainable agriculture is this: creating a closed system. Reliance on hybrid seed and external inputs is not sustainable. It is a system designed for the sole purpose of putting money into the pockets of multinational corporations.

Sustainable food production on a commercial scale requires animals. As gardeners, there are a host of plants that we may rely upon for fertility, to the degree that our external inputs can be limited to a few bags of fish bone meal and locally composted manure.

Comfrey, chamomile, nettles and yarrow are indispensible plants in the permacultural landscape. These plants serve multiple functions in the garden, but most notably that of fertilizer and mulch. They are easily grown perennials and self-seeders. Additionally, Lychnis viscaria has recently been a subject of study for its brassinosteroids, plant hormones that affect the health and disease resistance of several species common to our gardens. Generously dedicate space to these nourishing plants before any others.

Flowers as an Insectary Device

Every ecosystem on Earth exhibits not only diverse plant species and their associated mycorrhizal and microbial communities, but diverse animal life as well. Insects not only pollinate, they are predatory, and though it may seem counterintuitive, the greater the diversity of insects in your garden the less likely your food plants will succumb to insect damage. The easiest way to lure this beneficial wildlife to your garden is with flowers.

There are several species of perennial flowering plants that belong in an insectary garden, but there are also many annuals whose culture is far less demanding. Do not thumb your nose at the inclusion of annual species in a permacultural landscape. Annuals exist everywhere in nature and manage to propagate without the benefit of humans. Furthermore, let us not forget that humans are indeed part of nature, and that our efforts to select and maintain annual species from year to year is ecologically sound. This symbiotic relationship suits us as well as the plants. 

Include as many species of flowering plants in your landscape as possible. Consider a rather conventional “border" of flowering plants along the edge of your garden. Begin with a backbone of tough, perennial Helianthus maximiliani. Wild Fennel (Foeniculum vulgare) flowers are an insect and butterfly magnet and make an effective trap crop for hornworms. Cosmos bipinnatus are ubiquitous for good reason, and they are indispensible in the insectary border. Early perennial bloomers like Aurinia saxatilis and Allium hollandicum or Allium aflatunense are crucial. Vining Nasturtium species can make a good trap crop for aphids.

Some flowers belong alongside food crops. Lobularia maritima should be planted among the lettuce and carrots to lure tiny parasitic wasps. Perennial Chamaemelum nobile is thought to increase the resilience of neighboring garden plants and increase the essential oil content of herbs and medicinals. Diminutive edible flowers like Calendula and Viola species belong among the salad plants. Some Tagetes species repel nematodes and should also be planted amongst the vegetables.

Gardeners in the US and Canada would do well to include several species that feed our native bumble bees: Monarda, Aster, Nuttallanthus, Apocynum, and Solidago are just a few of the native genera that can be incorporated into a dry insectary border. For more information on our native pollinators please visit: https://beecology.wpi.edu

Copyright @ 2019 Marianne Schmidt, All Rights Reserved