- Author: Robin Rowe
I just returned from a 10-day camping vacation. It seems whenever I am away the temperature reaches triple digits. This year proved no different, except wondering how our recently planted citrus and avocado grove on the very exposed south side of the house endured. When we planted the young trees this spring, all sorts of folks felt the need to pull their cars up to the curb and tell us what a bad idea it was to plant trees where they would get sun and wind exposure. We smiled and said, “thank you!” not fully understanding the impact of our tree placement.
When we returned from our trip and drove up to the house, we were happy to see the citrus trees were doing just fine, but those avocado trees were totally stressed out!
So, I am asking myself, did I really do the research I needed to do before planting this young grove between the street and my house? Have I done all I can to help my newly planted trees get through the hot summer? Here are a few things I have learned this week:
1. One of the best ways to avoid heat damaged trees is to select species adapted to one's climate. Were avocado trees a solid choice for my Sunset Zone? Here is how to identify your climate zone: https://www.sunset.com/garden/climate-zones/sunset-climate-zone-los-angeles-area
Newly planted trees are the most heat-susceptible plants. The roots have not had a chance to become established. Turns out citrus and avocado thrive in my climate zone; however, it would be helpful to shade them from the sun and wind while they are young.
2. Before we left, I established a regular watering program with drip hoses and a timer as I have not yet installed my permanent irrigation. It is best to water early in the morning. Keep the tree trunk dry and water outward toward the drip line of the tree.
There is a condition called ''physiological stress' which results from a plant losing water (from transpiration) faster than water can be taken up by the roots, even if enough water is available. This occurs often late in the afternoon of a hot day. Further watering will not help and can lead to root rot unless the roots are truly dry! Check the roots several inches deep to find out how dry the soil actually is.
3. Mulch would have been very helpful, and I neglected to apply the desired 3-4 inches. Keep mulch several inches away from the trunk and remember to replenish it as it breaks down. The mulch keeps soil moisture in and weeds out and buffers soil temperature reducing heat stress.
4. Once trees are stressed from drought or heat, they often succumb to other stressors, such as insects and fungal diseases. Keeping trees healthy is essential. I will need to keep a closer eye on these trees while they recover.
While avocado and citrus are traditionally grown in where I live, there may have been better choices. On the UC ANR Green Blog, ‘UC study seeks street trees that can cope with climate change' is a very interesting piece y authored by Jeannette E. Warnert, reporting on an ongoing research study by UC Cooperative Extension scientists partnering with the U.S. Forest Service. The article also provides a sampling of trees that are part of the study. The following two sites are useful for tree selection for your climate zone: http://calscape.org/(natives) and https://selectree.calpoly.edu/(natives and compatible non-natives).
- Author: Robin Rowe
Sandy Szukalski and I enjoyed a visit to the McKinley Elementary School Garden this past week. Virgina 'Gin' McMillin, the Garden Director had an amazing amount of enthusiasm for the garden, the children, her IERCD grant, the future pollinator garden and just the future of the McKinley school garden in general is was infectious!
Gin asked us to come visit so she could show us her failing pumpkin plants and get some advice. It seemed as if the plants were not going to thrive. They were undersized, yellowing, and had a bit of fungus. The pumpkins were planted by the children on Earth Day (late April). The school district had provided a 50/50 mix, but it seems as if it was not very nutritious and may have had unhealthy plant material. The plants were also planted too close together for pumpkins.
Below is a summary of the information we shared with her and a few more bits that I hope will help your pumpkin garden thrive:
- Build up mounds for each plant - plant mid-July - August depending on growth projections. If pumpkins ripen on the vine too early they may get fungal rot.
- Plant plants 6-8' apart, using 3-5 seeds in each mound. Heavily mulch.
-Introduce nice soil to the pumpkin mounds. Especially if your current soil is not very nutritious.
- Use mulch to help keep moisture in and reduce weeds. That will also provide a nice bed for pumpkins later.
- Once plants germinate and are 2-3" tall, begin thinning out less healthy plants, leaving the healthies 2 plants.
- Pumpkins need to be fed. Use nitrogen for early plant growth then when the plants are larger but before they bloom she should use phosphorus. Alternatively, you can use the more easily accessible forms such as coffee grains or manure. Feed at regular intervals.
- Water in the morning (keeping the soil moist until germination), and if it gets very hot, in the afternoon as well. Water deeply 1".
- Be patient for fruit - mail and female blossoms are needed. Don't use insecticide. The plant needs bees.
- Snip off fuzzy ends of vine after a few pumpkins have formed to focus plant energy on fruit. Pruning vines will help with that as well. As fruit develops, turn (with great care) to encourage nice shape. Slip a thin board or plastic mesh under pumpkins to protect them.
- There is an excellent problem diagnosis for pumpkins from 'California Master Gardener Handbook', page 394 and a list of recommended varieties from page, 395. This book - it has a wealth of information!
Happy Gardening - stay hydrated!
- Author: Michele Martinez
Encouraging healthy bee populations has long been part of the Master Gardener mission. In our study of Integrated Pest Management (IPM), we learn that chemical pesticides can do harm to entire food chains, from plants to insects, and other wildlife. With bee colony health very much in the news, many gardeners are surprised to learn that in addition to the European honey bee, California is home to hundreds of species of native bees, many of whom reside in solitary nests, hidden in plain sight around our gardens. On a recent walk through a local apple grove, I was excited to identify four – maybe five types of native bee hovering in the blossoms alongside the honey bees. We know that plants and bees rely on one another for their existence. Recent studies published by the UC Cooperative Extension can help us recognize our native species, and help raise awareness about preserving bee habitats.
How do we identify native bees in the garden? The 2009 report Native Bees are a Rich Resource in Urban California Gardens presents findings of a UCANR study done in collaboration with the North American Pollinator Protection Campaign and the Xerces Society. Over three years, scientists surveyed bees in seven urban areas across the California, including La Cañada-Flintridge, near Pasadena. Of an estimated 1600 native species currently known in California, 60 to 80 species were observed, along with the plants that attract them. The study shows which native bees are likely to show up in our gardens.
Of the species counted, the most common was the ultra-green sweat bee (Agapostemon texanus). To spot this bee it's important to look closely. With its smooth green body and slender shape, the sweat bee can be mistaken for a fly. The photos from the UC study by Rollin Coville (©2009) show a female ultra-green sweat bee (above) and a male (below) as they feed on native blooms.
Another common visitor, the leafcutting bee (Megachile perihirta) has a distinctive mandible designed for chomping stems and leaves.
The digger bee (Anthropora edwardsii) is prevalent in Southern California and is specifically adapted to the tiny flowers of the native manzanita (photo at top of article) (Arctostaphylos sp.). Like many native bees, the digger bee is solitary. The female prefers dark quiet places to lay her eggs, and makes her nest in dead wood, or in the ground.
Unlike the male of most bee species, females have specially formed hind legs made for gathering pollen. During springtime's brief blooms, native bees can be seen going from flower to flower loaded up with the golden powder. This solitary bee (Svasta obliqua expurgata) is a muli-tasker, as she simultaneously sips nectar and collects pollen on a coneflower (Echinacea pupura).
The native bees to look for in our gardens this season include those counted in the study: mining bees (Andrena angustitarsata); digger bees (Anthrophora); and three bumblebee varieties (Bombus), California, black-tip and yellow-faced. Others bees found include carpenter bees (Ceratina); gray digger bees (Habropoda depressa) and long-horn digger bees (Melissodes), as well as squash bee (Peponapis pruinosa); cuckoo bees (Xeromelecta californica); large carpenter bees (Xylocopta tabaniformis incompletes); leafcutting bees (Megachile); mason bees (Osmia coloradensis); and the blue orchard bee (Osmia lignaria propinqua).
Learn More About Bees
The Xerces Society's The Citizen Scientist Pollinator Monitoring Guide was created to help communities as they survey pollinator populations at the local level. The user-friendly guide (see link, below) helps gardeners learn the basics about bees, identify different varieties, and track their activities, over time:
http://www.xerces.org/wp-content/uploads/2010/06/CA_CSM_guide.pdf
The UCANR publication, Native Bees are a Rich Resource in Urban California Gardens is available online. It details some of the native plants that attract native bees, and help them thrive (California Agriculture 63(3):113-120 (2009)):
http://calag.ucanr.edu/Archive/?article=ca.v063n03p113
Credits:
All photos are by Rollin Coville (© 2009), used by permission of the Regents of the University of California.
Information on Native Bees:
North American Pollinator Protection Campaign
The Xerces Society for Invertebrate Conservation
Getting to Know our Native Bees
- Author: Michele Martinez
San Bernardino County Master Gardeners and Fruit Preservers brought their Fruit Trees, Drought Efficient Trees and Shrubs Seminar to the Crestline Library, on Saturday, February 24. The well-attended workshop provided information tailored to the gardening needs of mountain residents.
Yucaipa Master Gardeners Jillian Kowalczuk and Adam Wagner began the day with fruit trees. Why do some trees love the mountains more than others? Looking around our neighborhoods, we see many healthy apple and cherry
Tree Selection & Care
Among cool weather-loving trees, we have many choices. The local nursery staff can help identify trees best suited to the specific area. Today new varieties are developed for flavor, tree size, and hardiness. They range from tasty hybrids, to dwarf trees that give fruit that can be harvested from the ground, without using a ladder. Once you have settled on the right tree, Jillian and Adam offered best-practices for preparing soil, planting, and caring for the tree. Nursery-bought trees don't always arrive in top condition, especially container trees which may have crowded or damaged roots. Bare-root trees are often less expensive, and can be easier to establish. Jillian and Adam concluded with tips on setting up drip watering for fruit trees, and pruning methods that promote both healthy trees and bountiful harvests.
Fruit Preserving & Canning
San Bernardino County Master Food Preservers is a sister program to Master Gardeners. Once we establish our
Finding the Right Plants for Mountain Locales
Local Master Gardeners Shelly Eagan of Big Bear, and Ken Witte of Lake Arrowhead, led the afternoon session with a focus on sustainable practices for mountain gardens. Shelly is a garden and landscape designer with a wealth of experience helping mountain residents select and care for trees and shrubs. Among her tips was to have your correct USDA and Sunset zone information in hand when choosing plants. In communities from Big Bear to Running Springs, Lake Arrowhead to Crestline, Shelly pointed out, there are a variety of zones, and several micro-climates can exist side-by side in our own yards. In observing such factors as wind direction, slope versus flat land, filtered or reflected sunlight, and so on, we can map our yards for hydro-zones, where plants are grouped according to water needs. Shelly gave examples of tried-and-true trees and shrubs, reminding participants that though a tree or shrub may be labeled “drought resistant,” new plantings need to be watered in the first two years, so their roots can take hold. Trial and error is part of the game for mountain gardeners, and attendees shared stories of hard-to-grow plants. Ken Witte concluded the day, sharing his work with the Heap's Peak Arboretum in Sky Forest. The Rim of the World Interpretive Association has collaborated with local scout troops to place educational signage along the trails at the Arboretum. Ken showed a series of Internet-based resources that feature mountain ecology, with information on native plants and their animal communities. For those of us hoping to establish native gardens at home, the Arboretum demonstration garden is a tremendous resource. While walking the trails, we can observe plants, birds, and insects in their ideal habitats, and figure out what species might suit our micro-climates. The Heaps Peak Arboretum offers a bi-yearly native plant sale, and is open year-round to visitors. Ken's information on mountain species is available at the Heap's Peak Arboretum web site: http://www.heapspeakarboretum.com/.
- Author: Michael Bains
We have a couple of upcoming seminars starting this Saturday in Chino Hills and Crestline. Hope to see you there.