Saturday sales - sustainable plants!

M R Gardens opens its greenhouse to the public on most Saturdays April through June 10, with sales from 9 a.m. to 4 p.m. We are also open by appointment in the early evenings on weekdays.

We aim for "as sustainable as possible," which means not only using organic methods but also growing in a passive solar greenhouse heated entirely by solar gain and cooled with manual vents.

Fireweed - Chamerion angustifolium. Native, beneficial, medicinal and edible. 

This page is updated weekly with current availability.

Vegetable starts: Tomatoes! including slicers, cherries, plums (like Romas, which are good for canning), and salad tomatoes. We have heirlooms and disease-resistant varieties. Also, sweet and hot peppers, eggplant, ground cherries, tomatillos, Swiss chard and sorrel are in stock.

Culinary herbs: Rosemary, basil, parsley, thyme, marjoram

Ground covers: Roman chamomile, alyssum, creeping thyme, marjoram

Southeast native perennials (all started by seed): Bee balm (Bradbury's), Carolina bush pea, culver's root, Coreopsis, early sunflower (Heliopsis helianthoides), fireweed, Liatris, Lobelia (great blue), mountain mint, rattlesnake master, two varieties of Rudbeckia, including a bicolor daisy, vervain (Verbena stricta), white doll's daisy (Boltonia), and several types of asters.

Medicinal herbs: Many of the plants listed in the natives and ground covers sections have medicinal properties. In addition, we have angelica, ashwagandha, balloon flower, catnip, comfrey, gotu kola, hyssop (Hyssopus officinalis as well as Agastache), lavender, stinging nettles, tulsi, valerian. We can also can have yarrow if you give us two weeks notice.

Plants that benefit the garden: Almost all of the plants listed as ground covers or medicinal and native plants attract beneficial insects to the garden (i.e. pollinators or predators of pests). In addition, comfrey's leaves provide "green manure" or fertilization, and official hyssop is said to confuse cabbage worm moths to keep them away from Brassicas. 

Find us at 441 Onteora Blvd., Asheville in the Oakley community. Contact megan@mrgardens.net or 828.333.4151 (office line) with questions or to set up an appointment. You also can reserve some of the plants on https://squareup.com/store/m-r-gardens.

Lavender - L. angustifolium

Hyssop - H. officinalis. Medicinal and beneficial.

Alyssum - "Royal carpet" has a mix of white and light purple flowers

Comfrey's leaves can be used as a green manure in the garden

Angelica - medicinal herb and beneficial flower

Greenhouse tours on Saturdays

Passive solar greenhouse tours, Saturdays at 11a.m., April 8 until June 10. Please RSVP.

M R Gardens is offering tours of the nursery’s one-of-a-kind passive solar greenhouse, designed for the production of plants using nearly all renewable resources. The 40-minute tours are at 11 a.m. Saturdays from April 8 to June 10. The information given on solar design and seedling propagation is helpful for all experience levels—novices as well as avid growers.

As printed in the Asheville-Citizen Times

M R Gardens Owner Megan Riley aspires to grow plants that are as sustainable as possible. Growing seedlings with practically no supplemental heat or high-powered exhaust ventilation is a big step toward that goal.

"Sustainability first inspired me to go into the agricultural field more than 15 years ago," Riley said. "But greenhouses aren't always energy efficient. If not designed carefully, they can use a lot of energy.”

Riley grows plants for clients of her native and edible landscape design and garden coaching services. Customers can also order vegetable, herb and flower starts through the M R Gardens website prior to the start of the season or attend plant sales on Saturdays at the greenhouse in spring and fall.

It is rare to find a passive solar greenhouse as large as M R Gardens' 800-square-foot house, especially one used solely for a plant nursery. While growers have experimented with similar structures since at least the 1960s, most of them are backyard hobby greenhouses for producing food in the ground year-round. A few small vegetable farmers incorporate passive solar techniques in their greenhouse designs, but not commercial growers in the nursery trade.

When laypeople think of solar design, they often picture solar panels with photovoltaic cells which convert sunlight to electricity. But a passive solar greenhouse does not necessarily need these panels. The building remains warm because water in barrels store heat collected on sunny days and then emit it when outside temperatures fall.

M R Gardens’ passive solar greenhouse on January 7. Outside, daytime temperatures were 20 degrees, while inside it was 85. Overnight, the lowest it dropped inside was 45, even when temperatures fell to 10 degrees the following night.

For optimal solar gain, the south-facing roof slants at a 55-degree angle so that the bottom edge nearly reaches the ground, ending at a three-foot high kneewall. On the north, west and east sides of the building, thickly insulated walls prevent heat from escaping.

The specific angles of the building determine how much sun rays enter the building at various times of the year. When deciding the specifications of the design, Riley considered the time of year she’d be using the greenhouse the most and what type of vegetation she’d be growing.

In the spring, the greenhouse remains within the range of 55 to 85, which is ideal for the summer transplants Riley is growing at that time. In the winter, it rarely drops lower than 50 degrees, suitable for the native perennials, herbs and spring vegetable starts in the greenhouse then.

The structure is also designed so that it doesn't overheat on late spring and summer days. As days lengthen and the sun is high in the sky, it moves above the slant of the roof, and less direct rays enter the house. Vents along the sides, front kneewall and roof peak ensure adequate air circulation.

Vents along the sides, front kneewall and roof peak ensure adequate air circulation so that it doesn't overheat on unseasonably warm days.

To open the roof vents, Megan stands on a stool and lifts up wood poles that hold the vents in place.

The water barrels not only emit heat during cool nights but also regulate the temperature on hot days. "It's like living next to a body of water, where the temperature fluctuations are less extreme," Riley said.

The 2017 winter offered ample opportunity to put the design to the test. On unseasonably warm 60 to 70 degree days, the greenhouse remained below 90 degrees as long as all the vents were opened at sun-up. The greenhouse also stayed sufficiently warm during short, cloudy, cold days of early January. The five inches of snow on January 7 was proceeded by several overcast days with little sun to warm the barrels. Yet even when it dropped to 20 outside, the minimum temperature inside at night was 45 degrees. These results were repeated the following night when the outside thermometer dropped below 10 degrees.

Heating a conventional greenhouse costs $4 to $5 per square foot in the course of the winter. That equals approximately $4,000 per year for a building of similar square footage. That number does not include the large expense of powering exhaust fans that are typically on the ends of greenhouses. Over time savings in these energy costs make a passive solar design economically feasible.

While sustainability is the primary goal of the project, Riley has found that the greenhouse has other benefits. "It's an ideal environment for seedlings,” said Riley, who has been growing seedlings for sale since 2011. “The plants grow faster and are an even higher quality than past years.” She explains several theories why it’s such a good growing space during greenhouse tours.  

Inside the greenhouse early April 2017

Please RSVP by contacting megan@mrgardens.net or 828.333.4151. Tours are offered at a sliding scale with a minimum of $5 per person. Note: May 20 we will not hold a greenhouse tour because we will be at the Black Mountain Garden Show and Sale. Join us at an alternate time: Monday, May 22 at 4 p.m.