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Elinor Teague

Welcome Elinor Teague

Elinor Teague
A note from Elinor Teague to the readers:  After writing gardening columns for the Fresno Bee for 18 years, it is a pleasure to be able to continue to offer readers gardening advice and tips here on the Fresno County Master Gardeners’ website. 

Catch her on KYNO for the "Master Gardener Minute" on Friday, Saturday, and Sunday at 7:40am, 1:40pm, and 5:40pm. 

Readers’ questions and comments are always welcome. 

Our Garden Helpline is working remotely by e-mail only.

 Questions? Send an email to mgfresno@ucanr.edu 

Including photos is helpful.  We are looking forward to hearing from you!

 

  • Climate change prompts re-thinking of garden planting schedule

    Jan 1, 2025

    There have been many changes in the sources and availability of plants and transplants over the last five to ten years. Several economic downturns as well as the pandemic forced the closures of many independent, locally owned nurseries. Big-box garden centers are often the only nearby source of plants for home gardeners. Garden centers tend to stock only the most popular, best-selling varieties and species, many of which are not heat- and drought-tolerant. The best and most reliable sources for seeds and live plants that can withstand and thrive in our extremely hot and arid Central Valley climate are increasingly easier to find online. 

    Many home gardeners aren't yet accustomed to starting their plants from seed or buying their plants online, but it is becoming the most practical way to be assured that the varieties and species in our gardens are suitable for our growing conditions. Seed companies and growers that offer plants online usually provide much more detailed information in their catalog descriptions than can be found on garden center labels. Many also sell the grow lights, heat germination mats, seed starting soil mixes and biodegradable or reusable small pots that make seed starting an easy, reliably successful yearly process.  

    Observation is making it clear to home gardeners that our climate is consistently hotter and drier than in past years, making gardening more challenging every year. Rising temperatures and a continuing pattern of drought have necessitated a complete review of plants' ability to survive extreme weather conditions. 

    Our summer growing season now begins about two weeks earlier than in past years. We'll need to start seeds and cuttings for drought- and heat-tolerant perennials and summer annuals and vegetables in the first week or two of January for transplant into the garden six to eight weeks later in mid- to late-March. Transplants should be in planting beds or containers by the first week of April since the hot spells that used to arrive in May have begun to arrive in late April.  We've also had extreme heat spikes in mid-summer continuing into September and October.  Home gardeners should be noting which species and varieties of summer-blooming annuals and summer vegetables are better able to survive long periods of high temperatures. When replacing old favorites with native plants or varieties that are labeled as “early crop,” “slow to bolt” or “heat resistant,” take note of their success rates as well.

    The fall recovery period seems to be shortening as our summers grow longer and hotter. Gardeners used to be able to count on a second early fall crop from summer favorites like indeterminate tomatoes, beans and cucumbers as temperatures cooled and plants recovered their vigor in late August and early September. That recovery period now begins in early October, if at all. Planting determinate tomatoes with a shorter growing season and planting flower and vegetables varieties with fewer “days to maturity” earlier in the spring may well become the norm as gardeners adjust to changing conditions. 


  • Horticultural oils are useful garden tools

    Dec 6, 2024

    Horticultural oils are great tools for controlling and reducing pest insect populations and for treating fungal problems.  The oils kill on contact by coating and suffocating the larvae, eggs, adults and nymphs of soft-bodied insects, including aphids, whiteflies, scale, leaf-miners and red spider mites. They also disrupt the insects' summer feeding patterns.

    In winter, when sprayed on fully dormant trees and bushes, the oils further reduce pest insects' populations before they become active again in spring. When added to the regular practice of good garden sanitation (cleaning up litter, weeds and pest-infested leaves and debris as well as picking up fallen fruits and removing dried fruit mummies from bushes and trees) home gardeners should see very few, easily manageable infestations of soft-bodied pest insects.

    Horticultural oils can also act as preventative fungicides. The oils coat leaf and stem surfaces, smothering the spores or pathogens and preventing them from attaching to the tissue and germinating. Success in controlling fungus problems depends greatly on the type of fungus being treated, weather patterns and timing of applications. Powdery mildew and black spot seem to be more easily controlled with applications of horticultural oils than rust or botrytis.    

    There are several weights and types of horticultural oils available to home gardeners and label descriptions often use terms that can be confusing. Horticultural oils can be formulated from petroleum-derived mineral oils or can be plant-based, such as neem oil, jojoba oil and canola oil.  

    Superior and supreme oils are interchangeable terms. Both are light weight, highly refined mineral oils and do not contain sulfur, which can harm sensitive plants. Supreme and superior oils can be applied when plants have leaves.  Some newer formulations of dormant oils are now labeled as supreme or superior oils. Dormant oils not labeled as supreme or superior should only be applied during the winter dormancy season.

    Dormant oils are slightly more viscous or heavier than summer-weight oils and are sprayed on deciduous plants and trees in winter when the plants are fully dormant and leafless, before bud break in spring. Applying heavier-weight dormant oils in summer when temperatures are high risks burning plant tissues.

    Summer oils are a type of superior oil. They can be applied in every season but might not be as effective as dormant oils in winter or during spring rainy seasons.

    Year-round oils can be safely used in every season. Check labels for temperature ranges. Neem oil is a year-round oil, as are superior oils.

    Horticultural oils should be sprayed to drench every surface – the undersides of leaves, branch crotches and bark cracks.  They are ineffective during freezing weather and can cause damage to plant tissues when temperatures are above 90 degrees. Labels provide information on application rates during every season and also list plants that are sensitive to the specific horticultural oil.

    Horticultural oils should not be sprayed on drought-stressed plants. Monitor soil moisture levels and deep irrigate trees and bushes that may be drought-stressed before applying horticultural oils. During our hot summers do not spray plants when they are in full sun even if temperatures are below 90 degrees.

    Sources:

    Monterey Horticultural oil, GrowOrganic.com

    Oils: Important Garden Pesticides, Pests in the Urban Landscape Blog. Author: Mary Louise Flint, March 11, 2014

    Horticultural oil spray: How dormant oil works, EpicGardening.com, June 20, 2023




Read Elinor's past articles