- Author: Pamela Kan-Rice
“Mature fruit trees and landscape trees are worth saving!” said Janet Hartin, UC Cooperative Extension advisor. “Recognizing early signs of drought stress is important because irreversible damage can occur that no amount of watering will correct.”
Two seasons without enough water can result in severe drought stress and even kill a tree, warned Hartin, who serves San Bernardino, Riverside and Los Angeles counties. Also, drought-stressed trees are more prone to damage from diseases and insects than non-stressed trees.
Common symptoms of drought stress include
- Wilting or drooping leaves that do not return to normal by evening
- Curled or chlorotic (yellow) leaves that may fold or drop
- Foliage that becomes grayish and loses its green luster
- New leaves that are smaller than normal
“One or two deep irrigations with a garden hose several weeks apart in spring and summer will often keep these valued plants alive, especially if their roots are relatively deep,” she said.
“An important thing to consider when you're trying to conserve water in the garden and landscape is that plant water requirements vary,” said Hartin, an expert in environmental horticulture. “Water needs are directly related to the evapotranspiration rate of each particular plant. To meet the water needs of plants, you have to replace the water used by the plant and the moisture that evaporates from the soil surface.”
Besides differences among water requirements among plant species, microclimates within a climate zone affect how much water a plant will need and how often a plant should be watered, as well.
“Landscape plants in urban heat islands surrounded by asphalt parking lots may require 50 percent more water than the same species in a park setting,” Hartin said.
Also, soil type plays a large role in how often landscape and garden plants should be irrigated. Sandy soils drain faster and take water in faster than those containing clay and require more frequent irrigation. Water can soak down 12 inches in 15 minutes in sandy soil, whereas the water may take 2 hours to reach the same depth in clay soil and will spread out more horizontally.
“Dig into the roots,” she said. “Take a handful of soil and squeeze it. That'll give you a good idea of whether the soil is really dry and crumbly, which means it's not holding any water, or if it's medium, where it's just starting to crumble, but still holding together fairly well. We recommend waiting to irrigate until the soil just starts to crumble.”
To see a video of Hartin's presentation “How to Save Water and Beautify Your Landscape the Sustainable Way,” visit https://www.youtube.com/watch?v=MN4b5DML-bs. For water-saving gardening tips in Spanish, visit http://bit.ly/1uZ6Ztq and http://bit.ly/1xHNwQo. You can also consult the UC Master Gardeners in your community for advice. Check http://camastergardeners.ucanr.edu to find the nearest UC Cooperative Extension office to speak with a Master Gardener.
Factors involved in irrigation scheduling
- Plant water use
- Soil water holding capacity
- Water infiltration rate
- Plant rooting depth
- Irrigation system output
- Author: Diane Nelson
“Sales of fruits and vegetables have remained strong, even during this recession when sales of other plants have lagged,” said Ron Hoffman, owner of Morris Nursery in Riverbank, Calif., echoing the sentiments of many in the state’s nursery industry. “People enjoy growing their own produce and they want plants that do double duty.”
And when they choose brightly colored edibles — like, say, Neon Lights swiss chard or Bronze lettuce — they can have their landscape and eat it, too. But designing and maintaining an edible landscape is easier said than done. How do you know what plants to choose? What if one plant needs different soil and more water than its neighbor? How do you keep the cat from pooping on your produce?
The folks at the UC Cooperative Extension Master Gardener Program, with assistance from California Center for Urban Horticulture at UC Davis, are answering those questions and many more at 6 two-day, “train the trainer” workshops throughout the state. Funded by a two-year grant from UC Agriculture and Natural Resources, the program teaches the art and science of edible landscaping to master gardeners who, in turn, will help train the rest of us.
“Before you install an edible landscape, you need to assess the site and the user,” said Missy Gable, program manager for the California Center for Urban Horticulture. “How much time do you have to devote to gardening? What are your harvest needs? We brought together experts from diverse fields such as landscape architecture, horticulture, food safety and water policy to provide an overview of what’s possible with edible landscaping.”
The workshops are inexpensive — $35 for master gardeners and $65 for industry professionals. In exchange for their reduced rate, master gardeners sign an agreement to teach two classes within three months of their training — one for fellow master gardeners and one for the public. Cheryl Buckwalter, a professional landscaper and executive director of EcoLandscape California, attended an earlier workshop and called the experience “invaluable.”
“Today's landscapes need to work harder than ever,” Buckwalter said. “They need to be water and resource efficient, functional and aesthetically pleasing. The Edible Landscaping Workshop not only showed me how to design the multi-functional landscape of today by incorporating edibles, I also feel qualified to educate my clients, the public and other professionals.”
Will the workshops change the way people garden?
“As part of the project, we’ll be looking at that very thing,” said Pam Geisel, director of the UC Statewide Master Gardener Program and the project’s principal investigator. “We will evaluate the impact of train-the-trainer methodologies to determine whether participants adopt more productive, sustainable landscapes as a result of being trained or from training others.”
The benefits of edible landscaping are bountiful. Parents, for example, love exposing their children to both the joy of gardening and the value of healthy food. Farmers appreciate that more people realize produce doesn’t grow on grocery store shelves. But without a few pointers, it’s easy to err with edibles. Sometimes, for example, our eyes are too big for our stomachs.
“Like me,” Gable said. “I’m a plant nerd. This summer I bought four varieties of zucchini because they were so cool. Believe me, no one needs four varieties of zucchini.”
No two yards or gardeners are the same and the course helps people customize their plan to meet their needs. Do you work 12-hour days? Maybe it’s better for you to help out at a community garden than plant too many edibles in your own back yard. Is your garden in full shade?
“Grow blueberries,” Gable said.
There is still room in four Edible Landscaping Workshops this fall: Oct 11-12 in Santa Clara; Oct. 24-25 in El Cajon; October 26-27 in Los Angeles; Nov. 2-3 in Fresno; and Nov. 30-Dec. 1 in San Luis Obispo. You can register and find more details at http://cchu.ucdavis.edu/events/edible/edible
Media contacts:
- Pam Geisel, Director of the Statewide Master Gardener Program, (530) 865-1154, pgeisel@ucanr.edu
- Missy Gable, California Center for Urban Horticulture at UC Davis, (530) 752-6642, mjborel@ucdavis.edu
- Diane Nelson, UC Davis College of Agricultural and Environmental Sciences, (530) 752-1969, denelson@ucdavis.edu