MASTER GARDENERS March 2020 Issue In this issue Potting Mixes and Potting “soils” ..................................... 1 Dates for 2020 .................................................................. 2 Hamilton County Master Gardeners Public Classes..........2 Cumberland County Master Gardeners Programs ...........2 March: Whale's Tongue Agave ......................................... 3 April Gardening ................................................................. 4 Recipes for Potting Mixes ................................................. 5 Short Rows ........................................................................ 6 More on the plant of the month....................................... 6 Potting Mixes and Potting “soils” Sheldon D. Barker I came across a blog post (http://gardenprofessors.com/potting-soil- poison/#comments) about potting soil. My experience is that not all are equal. Jim Downer, with the University of California Cooperative Extension in Ventura County, author of the post set up a trial of the different media on sale and found: “There are usually about 18 to 20 different media on the market at any given time and the results of growing plants in them is predictable. About 10 of the media will not grow anything very well, 5 give ok results and about 5 of the products will grow a nice plant.” Part of the reason for this wide range of results was chemistry, specifically nitrogen. When a nitrogen source was added some of the media grew better plants, some even with the help would not grow plants. Another factor affecting the quality of the media is the ingredients used in the mix. Some contain manures which add a lot of salts to the media and adding fertilizer to boost the mix only makes matters worse. When buying a media a light fluffy mix would be better that a heavy mix. Look over the list of components, peat/peat moss and coir (coconut husk fibers) are common; avoid manures and forest products. http://gardenprofessors.com/potting-soil-poison/#comments See page 5 for recipes for DYI potting media.
Transcript
MASTER GARDENERSMarch 2020 Issue
In this issue Potting Mixes and Potting “soils” ..................................... 1 Dates for 2020 .................................................................. 2 Hamilton County Master Gardeners Public Classes .......... 2 Cumberland County Master Gardeners Programs ........... 2 March: Whale's Tongue Agave ......................................... 3 April Gardening ................................................................. 4 Recipes for Potting Mixes ................................................. 5 Short Rows ........................................................................ 6 More on the plant of the month....................................... 6
Potting Mixes and Potting “soils” Sheldon D. Barker
I came across a blog post (http://gardenprofessors.com/potting-soil-poison/#comments) about potting soil. My experience is that not all are equal. Jim Downer, with the University of California Cooperative Extension in Ventura County, author of the post set up a trial of the different media on sale and found:
“There are usually about 18 to 20 different media on the market at any given time and the results of growing plants in them is predictable. About 10 of the media will not grow anything very well, 5 give ok results and about 5 of the products will grow a nice plant.”
Part of the reason for this wide range of results was
chemistry, specifically nitrogen. When a nitrogen source was added some of the media grew better plants, some even with the help would not grow plants.
Another factor affecting the quality of the media is the ingredients used in the mix. Some contain manures which add a lot of salts to the media and adding fertilizer to boost the mix only makes matters worse.
When buying a media a light fluffy mix would be better that a heavy mix. Look over the list of components, peat/peat moss and coir (coconut husk fibers) are common; avoid manures and forest products.
http://gardenprofessors.com/potting-soil-poison/#comments See page 5 for recipes for DYI potting media.
Dates for 2020 • Soil Test Saturday, March 14 Pikeville, Farmer Market/ Courthouse 9AM till Noon • Soil Test Saturday, and Tree Day March 21, Dunlap, UT Extension Sequatchie County office 9AM till Noon • 2020 Flower, Lawn and Garden Show "Plant a Smile", April 24-25, 9am - 5pm Both Days Cumberland County
Community Complex, 1398 Livingston Rd, Crossville, TN $3 adults, Children under 12 are free; Master Gardeners free entrance with badge https://www.ccmga.org/2020flags
• Quarterly meeting and Spring Outing, April 18, Dunlap Coke Ovens, includes a tour of the Coke Ovens and a tree id walk
• Fruits of the Backyard – June 9, 8:30 a.m. CDT, Middle Tennessee AgResearch and Education Center, at Spring Hill • Green Industry Day – June 16, 8 a.m. EDT, UT Gardens, Knoxville • Summer Celebration – July 9, 8 a.m. CDT, West Tennessee AgResearch and Education Center, Jackson • Quarterly meeting, July 25, Pikeville, Tomato Tasting • UT Arboretum Butterfly Festival – August 1, 10 a.m. EDT, Forest Resources AgResearch and Education Center – UT
Arboretum Auditorium at Oak Ridge • Steak and Potatoes – August 4, 8 a.m. CDT, Plateau AgResearch and Education Center, Crossville • Fall Gardeners’ Festival – August 25, 8 a.m. CDT, Plateau AgResearch and Education Center, Crossville • Turf and Ornamental – August 27, 7 a.m. EDT, East Tennessee Center – Plant Sciences Unit, Knoxville • Organic Crops Field Tour – October 1, 9 a.m. EDT, East Tennessee AgResearch and Education Center – Organic Crops
Unit, Knoxville • Woods and Wildlife – October 15, 7 a.m. EDT, Forest Resources AgResearch and Education Center – Cumberland
Forest at Oak Ridge • Quarterly meeting, November 7, Pikeville
Other UT Field Days can be found at https://extension.tennessee.edu/WebPacket/Pages/NYCU-2020-01FieldDaySchedule.aspx
Hamilton County Master Gardeners Public Classes The Education Committee of the Hamilton County Master Gardeners offers a series of public classes on the third
Saturday of each month at 10:00 am. All classes are held at the AG center on Bonny Oaks Drive and are free unless otherwise noted. • March 21, 2020: “Trees: A How To” Presented by Tom Stebbins • April 18, 2020: MGHC Expo Weekend – JOIN US AT CAMP • May 16, 2020: “Daylilies” Presented by Peggy Dyer
June 20, 2020: “Herbs: Hot & Cool!” Presented by Katie Bishop • July 18, 2020: “Rain Gardens” Presented by Mike Payne • August 15, 2020: “Our Pollinators” Presented by Ann Brown • September 19, 2020: “Why Native Plants” Presented by Ron McKitrick • October 17, 2020: “Tool Care” Presented by Bud Hines • November 21, 2020: “Wreath Making Class” Presented by MGHC Leaders Please be advised there is a $5 fee for this
class payable at the door. Registration for the wreath making class will open on October 1. Registration details for can be found at https://mghc.org/education-committee-classes/
Cumberland County Master Gardeners Programs There is a long list of class offered by the Cumberland County Master Gardeners you can find a full list at
UT Gardens Plant of the Month March: Whale's Tongue Agave This Fast-growing Succulent is an Exotic Beauty Submitted by Jason Reeves, research horticulturist, University of Tennessee Gardens, Jackson
Up until about 15 years ago, only a handful of agaves were available that were hardy to zero degrees. On top of that, they were miniscule at only 3 to 10 inches tall and were not overly showy. They were nothing to get excited about. Whale’s tongue agave (Agave ovatifolia) was found in the mid 1980s growing in the Sierra de Lampazos Mountains in Mexico at elevations from 3,700 to 7,000 feet. It had not previously been described in any literature. In 2001 it was given the species name ovatifolia.
A fast-growing succulent, whale’s tongue agave is the personification of exotic beauty. The imposing blue leaves are arranged in a spiral—forming a single, symmetrical rosette. Whale’s tongue is grown from seed or tissue culture. Those grown from tissue culture (for
example, ‘Frosty Blue’ and ‘Vanzie’) are genetic clones and look exactly alike. Those grown from seed will differ in color, shape and size from plant to plant.
Colored in shades of blue, the leaves are cupped and can vary from long and narrow (24 inches x 8 inches) to relatively short and broad (18 inches x 10 inches). The grand, undulating leaves are lined with deep mahogany curved teeth measuring one-quarter to one-half inch in depth and end in a terminal 1- to 2-inch spine. Adding depth of beauty, a
shadow of these spines is left on each leaf from the emerging process. Agave ovatifolia will grow to 3 to 4 feet tall and 4 to 6 feet wide in 5 to 8 years, especially with summer water.
These plants end their life after 10 to 20 years with a spectacular show by producing a flower stalk 10 to 15 feet tall that draws a variety of bees. This stalk has many branches adorned with densely clustered chartreuse flowers, which are held upright, reminiscent of a candelabra. Unfortunately, the growing season in Tennessee is not long enough for the resulting seed pods to develop and mature before frost. Unlike most agave, it does not produce offsets (pups). Therefore, after flowering you will need to source another plant.
Whale’s tongue grows happily in soil with average to low fertility in settings with full sun to dappled shade. They are drought tolerant, but grow much faster with supplemental water in the summer. Even though they are more adaptable to damp, cool climates than other agaves, good draining soil is the key to success. They are best planted on a slope or in a bed amended with crushed gravel.
It is best to plant the zone 6b agave during the months of May through July, which allows time for the roots to become established before the following winter. The young plant should be shielded from winter rain for the first and second winters. At the UT Gardens, Jackson, we place a shallow clear tub (18 inches x 24 inches) upside down over the plants from December to early April. The tub has a dozen half-inch holes drilled near the top to allow air to escape on warm days. The tub should be elevated 4 to 6 inches above the soil for airflow. The goal is not to keep the plant warm but dry. In the fall and winter, be sure to remove any fallen leaves and debris that collect on or around it.
This striking succulent makes an exotic specimen in the garden and can be even more impressive when used in mass plantings. We enjoy them in our gardens and know you will, too!
A fast-growing succulent, whale’s tongue agave is an exotic beauty in the Tennessee landscape. The
imposing blue leaves are arranged in a spiral—forming a single, symmetrical rosette. Jason Reeves shows off a specimen at the UT Gardens, Jackson.
Photo courtesy UTIA. another picture on last page
Planting Instructions: For a large area remove the existing soil approximately 12 to 18 inches deep. Refill with a mix made of one-part excavated soil and three-parts crushed rock while building the entire area up 8 to 12 inches above the original level (grade). Crushed pea gravel, granite chicken grit and PermaTill®/ VoleBloc all work well. Mulch the plants with gravel instead of traditional mulch. When preparing the ground for a single plant dig a bowl-shaped hole 16 inches deep, fill with the soil-gravel mix and then mound 8 inches of above that. Envision a 2-foot sphere of the soil-rock mix with two thirds of the sphere in the ground and the remaining one third above. Then plant the agave at the top of the mound.
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April Gardening This is an action-packed month for gardening. Gardens are bursting with color from all of the flowering bulbs and
spring flowering trees and shrubs but you probably have weeds popping up everywhere as well. Temperatures are cool enough that its pleasant to work outdoors but its warm enough that perennials plants have broken their dormancy. This also is the month when we have our last frost making it a great time to plant annuals and vegetables. Following are some gardening ideas and suggestions to help you do the most for your garden this month: Shrubs and trees • You can prune summer flowering shrubs like Crepe Myrtle after the last extremely cold weather but before they leaf
out significantly. • Prune spring flowering shrub like forsythia, weigela, Japanese quince, and lilac within 2 to 3 weeks after the last petals
have dropped. Prune these shrubs at the base, near the ground to help rejuvenate its growth and keep it flowering heavy.
• Fertilize shrubs and trees if this wasn't done in February or March. Use an acid type fertilizer to feed evergreens, conifers, broad leaf evergreens, rhododendrons, azaleas and camellias. Use an all-purpose fertilizer to feed roses and other deciduous trees and shrubs. If you use granular type fertilizers, be sure to water it in thoroughly.
Perennials, annuals, and bulbs • Prune any semi-woody perennials like Salvia greggii, Lavender, Sage, Artemisia, and Careopteris. • Prepare your annual planting beds now so they are ready when you want to plant. The addition of well-rotted manure,
processed manure, peat moss or compost are good additives for building compost humus in the soil. I recommend not planting annuals until after April 15th, our average last frost-free date.
• Plant tender bulbs and tubers (gladiola, lilies and dahlias). You may continue planting additional bulbs every two weeks until mid-June to ensure a continuous source of bloom.
• Deadhead or remove spent flowers from spring blooming bulbs. Don’t remove foliage until it yellows or freely pulls loose when slightly tugged.
• Fertilize spring blooming bulbs just after blooming. A complete fertilizer such as 5-10-10 at a rate of 2 pounds per 100 sq. ft.
• If you noticed smaller blooms on your bulbs this spring, divide crowded planting as blooming finishes (especially daffodils).
• Watch for iris borer on your iris. For control, check with the UT Extension office. • Stake now, any perennials which lodge or fall over from the weight of their heavy blooms in late spring or summer.
Staking now will allow plenty of time for new growth to hide your support structures, preventing them from taking away from the beauty of your perennials.
• Stake clematis and any other vines which could use the added support as new growth emerges and they begin to flower.
Fruits and veggies • While fruit trees are blooming, refrain from spraying any insecticides to protect the bee population busy pollinating the
flowers. Within a week after petal drop, you can resume using any pesticides. • After petal drop, consider spraying your peach, plum, and cherry fruit trees for protection from fungal diseases like
brown rot, rust, and leaf spots. Maneb (also sold as mancozeb and dithane) works well for these diseases.
“Gardening requires lots of water - most of it in the form of perspiration.”
Lou Erickson
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• You can still plant these cool-season veggies this month: spinach, head and leaf lettuce, collards, turnip greens, onions, beets, broccoli, cabbage, Brussel sprouts, cauliflower, carrots, early potatoes, radish and Swiss chard can be direct seeded or transplanted into the garden.
• After April 15th, plant warm season veggies like tomatoes, peppers, and corn. Planting of the “high sugar” or sugar sweet corn varieties should be delayed until May 1st because the seeds do not germinate in cold garden soils.
Lawn care • For warm season grasses such as zoysia or Bermuda grass, April 15th marks your fist application of fertilizer. Use 1
pound of nitrogen per 1,000 sq. ft. • Until April 15th, its an ideal time to apply a combination of slow-release fertilizer and preemergent herbicide for
crabgrass control to your cool-season (fescue) lawn. You want to apply this combination before dandelions reach the puff-ball stage. The fertilizer will boost the growth of your lawn and have it looking great for summer and the herbicide will prevent crabgrass.
• Numerous brands are on the market and whichever you select, be sure to follow label directions. Odds and ends • Edge your garden beds. • Clean your pond or water feature and remove winter debris. Cutback and remove all dead plant debris from your
potted aquatic plants. Begin feeding fish around mid-April. • Pull weeds now while the task is easy and the weather is pleasant. You may find it easier to use a chemical like Round-
up to “spot” spray weeds in a flower bed. Be careful when using such chemicals to not spray it on desired plants. Round-up and its related chemicals are not selective herbicides and work by killing anything green.
• Its good to maintain a layer of 3"- 4" of mulch around your plants in your garden. Now is a great time to add any needed mulch to your garden getting it ready for the possibly hot and dry summer.
Recipes for Potting Mixes When making your own potting mix, working from a recipe is a good idea to start. Once you begin experimenting with your own blends, try small test batches to evaluate the mix’s quality. See the recipes below to get started making your own potting mixes.
Foliage Plants 2 parts peat; 1 part perlite; 1 part coarse sand OR 1 part peat; 1 part pine bark; 1 part coarse sand
Succulents 2 parts soil; 1 part peat moss; 1 part perlite; 1 part coarse sand
Bromeliads 1 part peat; 1 part bark; 1 part coarse sand
Seedlings 2 parts compost; 2 parts peat moss; 1 part vermiculite (pre-wet)
Soil-Based Mix This mix is heavier than peat-based mixes, but it has good drainage. Vermiculite or perlite can be used for sand. 1/3 compost; 1/3 topsoil; 1/3 sand
When using soil, use clean topsoil or garden soil that has been sterilized to kill disease organisms and weeds. Spread soil in a tray and bake at 200º F for twenty minutes, stirring every five minutes. Source: Homemade Potting Mix - UF/IFAS Extension https://sfyl.ifas.ufl.edu/lawn-and-garden/homemade-potting-mix/ Other references: “Homemade Potting Media” https://extension.psu.edu/homemade-potting-media “Potting Mixes for Organic Growers”, Vern Grubinger, https://www.uvm.edu/vtvegandberry/factsheets/pottingmix.html “Making Herb and Vegetable Containers” https://web.extension.illinois.edu/containergardening/herbveggie_media.cfm
Short RowsSnake oil for your snakes, and cures for your ills, we can find all kinds
of remedies for garden problems with a simple on-line search. So what works and what doesn’t? As Master Gardeners it is important that we share research and evidence-based information. So where do we find this information?
Start with a reliable source. UTHort.com is a great place to start links to UT Extension publications and factsheets can be found on this site.
There are other great sites as well, those ending with .edu, or .gov being those of universities and the government provide vetted and evidence-based research information.
The Garden Professors Blog at http://gardenprofessors.com/ is a great source of general horticulture information. Members of the Garden Professors Blog are Extension Horticulture Specialist. One of the interesting reoccurring themes on this blog is myth busting, what science really has to say about home remedies and other garden “lore”. Many of myth busting articles can be found at Linda Chalker-Scott Horticultural Myths https://puyallup.wsu.edu/lcs/.
Another great source would be the American Horticulture Society at https://ahsgardening.org/ .
More on the plant of the month
The Extension Master Gardener Program is a program of the University of Tennessee Extension
Sheldon Barker Extension Agent Sequatchie Co. 170 Church St
Dunlap, TN 37327 423-949-2611
UT Extension Sequatchie County web page Sequatchie County Facebook
J. C. Rains Extension Agent
Bledsoe Co. PO Box 289
Pikeville, TN 37367 423-447-2451
UT-TSU Extension Bledsoe County Webpage Bledsoe County Facebook
Useful links
Sequatchie Valley Master Gardening Program Link
TMG Volunteer Handbook link
This Photo by Unknown Author is licensed under CC BY-NC-ND
Whale's tongue agave is also cold tolerant, as shown in a night image by J. Reeves of the plant during a snow at the UT Gardens, Jackson. Photo
