- Author: Jeffrey P Mitchell
In an effort to extend information on CASI's twenty-year conservation agriculture study that has been conducted at the University field station in Five Points, CA and that has been recently published in the journal, California Agriculture, Jeff Mitchell provided three radio interviews on the morning Ag Report that Don York produces for KMJ580 AM each morning out of Fresno. The segments aired on May 23rd and on June 4th and 6th, 2024 and are available below. Mitchell shared findings of the long-term “NRI Project” that since 1998 has examined four production systems – standard tillage without cover crop, standard tillage with cover crop, no-till without cover crop, and no-till with cover crop.
The NRI Project started as an effort to determine the potential of reduced disturbance tillage in terms of generating or producing less dust and in the early 2000s found that dust can be significantly reduced by as much as 80% with a variety of reduced tillage practices relative to standard tillage techniques that have been widely used in annual crop fields throughout the San Joaquin Valley since the early 1930s. The recent findings from the unique long-term study have shown that several soil health indicators including aggregation, water infiltration, biodiversity, and surface carbon were improved through the long-term use of cover crops with reduced disturbance tillage.
In the interviews, Mitchell points out that the systems that were evaluated and developed in the NRI Project were not at all easy to implement and required considerable trial-and-error effort to achieve. Yields, for instance, of cotton in the early years under the high residue, no-till cover crop system lagged behind the standard tillage, however once effective planting techniques were learned to establish the cotton crop. There were no yield differences between the two tillage systems for the next several years.
The results of this study that included 18 coauthors can be seen at https://doi.org/10.3733/001c.94714
Jeff Mitchell on KMJ Ag Report 5-23-24
Jeff Mitchell on KMJ Ag Report 6-4-24
Jeff Mitchell on KMJ Ag Report 6-6-24
- Author: Debbie DiNoto
This month we will look at when and how to water your roses. Especially now that the weather is starting to heat up and the rains are probably done until the fall. We live in a Mediterranean climate. Winter rain and summer dry.
I am always asked how much water does a rose need? Ah, the typical Master Gardener answer is, “It depends!” It depends upon the time of year and the type/size of the rose. The typical hybrid tea (we are talking a big, tall and mature plant) will take 6 to 9 gallons a week if the temps are below 80 F (as in spring and fall). A rose bush, such as a floribunda, about 3 feet wide and tall, will need about 3 gallons a week if the temperatures are below 80F and it hasn't rained in a long time. In wintertime, when the temps are much cooler, they will take much less water, especially if we have rain or the plant is dormant. During this and last year's winter, I didn't have to water at all because of the rain we had.
When the temps are over 90 F consistently, they will take about 12 gallons a week (not daily!). Again, this will depend on the size of the rose. Mini roses will take much less water than a full-size hybrid tea. Roses are pretty drought tolerant and can take less water, but they may show signs of stress. Roses in pots will probably require more water during summer.
How can you tell if your rose is stressed by not getting enough water? They will drop their leaves, decrease flower size or show early signs of dormancy.
The amount of water a rose needs will also depend upon the type of soil you have (get your soil tested!). If you have clay soil, it will hold water, so you will need less. If you have sandy soil, the water will permeate more quickly through the soil, so your roses may need more water. If you have nice loamy soil, the recommendations above will suffice.
So what is the best way to deliver water to your roses? It is important that you deliver water efficiently. That means making sure there is no overspray if you are using sprinklers. If you are hand watering, use a water wand that you can turn off at the nozzle. When you are done watering one rose, you can stop the water flow before moving on to the next.
OK, here is where we get into the math of a drip system. How do you estimate the number of emitters each rose plant needs? It is not that difficult. If you use one-gallon emitters, that means that they will deliver one gallon of water per hour. If you place four one-gallon emitters per plant (an emitter in the front and back and one on each side of the plant), that plant will get four gallons of water per hour. We can water 3 days a week until the end of summer. So, if you run your system for an hour each day we can water (either Sunday, Wednesday, Friday or Tuesday, Thursday, Saturday depending on your address), your plant will get 12 gallons of water per week (three days per week x four gallons of water each day, equals 12 gallons per week).
OK, so one more bit of math. It is better for your plant not to get a gallon of water all at once. You want the water to soak into the soil surrounding the plant. I divide that hour of watering into three sessions of 20 minutes each. I stagger those times and water around 5 a.m., 7 a.m. and again in the evening after 7 p.m. Doing this allows the water to reach the roots of the plant. It also encourages the roots to grow deeply rather than on the surface. That is much better for the health of your plant.
Now, if the temperatures are going to be consistently over 107 F for several days, I may water a fourth cycle. I would add another cycle in the morning but keep the one at night as close to 11 p.m. as possible, so my plant can have some water for the next day or two when we can't water.
Mulch will moderate the temperature of the soil and maintain moisture. It will also keep weeds away from your plant! I prefer to do less work in the garden during our hotter than Hades summers. This is a way to make that happen! Don't use rubber mulch. Don't use mulch that has been dyed. Use a mulch that will break down over time and enrich your soil. I like fine wood chips the best. I will often have 2 to 3 inches of fine wood chips over an inch or two of compost around the plant. That way, I am feeding the soil, which the plant appreciates.
Now there are two thoughts as to whether to let your roses go dormant or not during a hot summer. For us, that generally means from the middle of June until at least the middle to end of September when the temps are finally cooler. If you choose to let your roses go dormant:
- Don't feed your roses.
- Make sure your watering system is operating efficiently and continue to water as described above.
- Apply 4 inches of mulch over the entire bed.
- Don't prune your roses.
- You can deadhead them or just remove the spent petals and allow hips to form.
- If the leaves burn on your plant, leave them on the plant to help shade the canes from burning.
There is another school of thought from folks who grow roses in Tucson. Grow your roses under shade cloth, when the temps are consistently over 95 F. June is often the hottest month in Tucson. They use 65% shade cloth as a canopy over their roses. In essence, they create a canopy structure with pipes and shade cloth. It is big enough to cover the roses and still walk under them. Some put a misting system on the pipe as well to increase the humidity.
They continue to feed their roses and don't let them go dormant. I have seen wonderful results. Beautiful growth and flowers all summer long. They remove the shade cloth in the fall, winter and early spring. In Tucson, they are still able to water their roses daily (if necessary and if they don't have monsoon rains that day). We don't have that luxury, unfortunately.
So, I will be trying a modification on this method. I just installed a pergola on my patio that will provide some relief during the summer (about 40% or so), near my rose bed. I may add an additional solar screen between my pergola and roses, so they get more relief from the blazing sun during the hottest part of the day. I will let you know how my “experiment” works!
Until Next Time; “I feel as if I had opened a book and found roses of yesterday sweet and fragrant, between its leaves.” – L.M. Montgomery, Anne of the Island
- Author: Lauren Fordyce
Pampasgrass (Cortaderia selloana) is a common ornamental landscape plant that readily naturalizes throughout California's coastal areas and some interior regions. Historically, pampasgrass was planted for erosion control, but it has since escaped cultivation and spread along sandy, moist ditch banks throughout coastal regions of southern California. Pampagrass can also grow in the hot, dry climate of inland areas of California.
A similar-looking invasive grass, jubatagrass (Cortaderia jubata), is more widespread, aggressive, and is a major pest in coastal redwood forest areas. Jubatagrass thrives in cool, foggy environments and does not tolerate temperature extremes or drought.
Both pampasgrass and jubatagrass outcompete native plants; a single floral plume can make 100,000 seeds in a year. They create fire hazards with excessive build-up of dry leaves, leaf bases, and flowering stalks. In addition, their tough leaves have serrated edges that can easily cut skin.
What can you do?
Choose non-invasive ornamental grasses to plant in your garden or landscape. Many species, including native grasses, can resemble pampasgrass or jubatagrass. This includes several species of Muhlenbergia: deer grass, white awn muhly, and Lindheimer's muhly. California native Pacific reedgrass grows well on the coast and is deer resistant. For a large, tough bunchgrass, try giant sacaton, a native of the Southwest. Giant wildrye, another California native, will grow into dense stands that attract birds.
To learn more about these invasive species and alternatives to plant, visit https://plantright.org/invasive/cortaderia-selloana/ or https://plantright.org/invasive/cortaderia-jubata/.
For more information on their management, visit https://wric.ucdavis.edu/information/natural%20areas/wr_c/cortaderia_jubata-selloana.pdf.
- Author: Terry Lewis
June days are the longest of the year - take advantage of the extra hours in your garden.
Tasks
- Check drip irrigation lines and emitters for leaks or clogs and adjust to provide adequate moisture.
- Thin fruit on stone and pome fruit trees.
- Spider mites can be discouraged by rinsing dust from foliage.
- Stake tall, weak-stemmed flowers.
- Cut spent canes to the ground after harvesting berries. Attach new canes to the trellis for next year's crop.
- Prune azaleas, camellias, and hydrangeas after bloom.
Fertilizing
- Reduce or eliminate fertilizer for landscape trees and shrubs, unless used to remedy nutrient deficiencies.
- Do not feed plants if they are water stressed.
Planting
- Limit planting during hot weather, as newly installed plants require frequent irrigation while root systems become established.
Enjoy now
- Annuals and perennials: Lily-of-the-Nile (Agapanthus), aster, fibrous begonia (Begonia semperflorens), Coneflowers (Rudbeckia).
- Bulbs, corms, tubers: giant allium (Allium), canna.
- Trees, shrubs, vines: abelia, desert willow (Chilopsis linearis), flowering maple (Abutilon).
- Fruits and vegetables: fuji apple, apricot, beans, eggplant.
Things to ponder
- Adjust lawn mower setting to cut lawn higher. Set mower to 2½ to 3 inches for tall fescue, ¾ inches to 1 inch for common bermuda, and ½ to ¾ inches for hybrid bermuda.
- Use less toxic insecticidal products such as insecticidal soaps or neem oil.
- Annuals such as pansies, petunias, and snapdragons are best planted in pots where they can provide a splash of color by an entrance rather than planted in beds where they will need more water.
- Author: Ben A Faber
Movento (spirotetramet) has been renewed for use on citrus Asian citrus psyllid in California. It's a foliar spray that is systemic especially moving to new tissue where ACP feeds. It also controls some other pests, such as thrips and leafminer. It has a short persistence effect on natural enemies and has low toxicity issues.
As an interesting aside, I just learned that cryolite (Kryocide, Pro-Kil) which was considered for organic registration at one time, has lost its registration. It was a stomach poison that worked on leaf-feeding beetles and lepidopteran pests like orange tortrix. The high level of fluoride necessitated its loss of registration.