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Peonys in Contra Costa County?

Client's Request: A visiting friend of mine has given me as a present a large 5 gallon Peony (Paeonia lactiflora 'Festiva Maxima'). These friends grow these back East, but I'm not familiar with Peonies or growing them here in Contra Costa County. Would you please provide me with some guidance on planting and caring for this Peony in my garden?

CCMG Response: Thank you for contacting Master Gardeners with your question regarding planting your new peony. How lucky you are to receive a five gallon Peony from a friend! Often a showy spring flower in colder Eastern gardens, they can also be grown in temperate Contra Costa County when situated properly in the garden.

Peony "Festiva maxima'
'Festiva Maxima' is an herbaceous peony that has huge, fragrant, pure white double flowers with vivid crimson flecks that can make for a showy bouquet in a white ceramic vase. The plant grows to 3 feet tall and wide and blooms in mid to late spring. It's one of the best peony for mild coastal climates, but unfortunately it can't take inland heat so you will need to choose a part shade spot for your new plant.

A permanent, morning sun only or partly shady site is ideal for your peony. Protection from afternoon sun and from harsh winds will help to prolong its life. Peonies will perform best in well-drained, evenly moist, rich soil with a pH near neutral. They are drought-tolerant once established. Hardiness Zone: up to 8 means that the cooler spring/summer  exposure the better and that cold exposure in winter isn't a problem. This most likely will lead to planting it with a north-easterly exposure in the garden trying to be “cool” in the summer at the same time trying to get adequate morning sun.

Peony 'Festiva maxima'
in the garden
Site Selection - choose carefully; peonies are long-lived and don't like to be moved!

  • Good drainage! Reasonably good soil!
  • Usually needs a sunny location for blooms - will do well in light shade but best blooms usually on those in full sun. In central and east county you will want a spot with morning sun and partial or afternoon shade (ideally 4-6 hours of morning sun).
  • Keep away from large trees or heavy shrubs to avoid root competition. 

Soil Preparation - important factor in growing peonies! Prepare well before planting!

  • Planting hole – Dig twice as wide as actual root size. Dig or till in a 2 - to 4 - inch layer of organic matter into heavy clay soil. Mix double handful of bone meal with soil for each plant. Sunset Western Garden Book also recommends letting the soil settle for a couple of days before planting.
  • Planting - Ideal time is early fall. Once planted, peonies can be left to grow undisturbed indefinitely. They may take 3 - 4 years to reach mature size; may not bloom first year and only a little the second

Watering – All peonies need regular water and should not be allowed to dry out. Apply 2 – 3 inches of organic mulch to retain moisture. 

Here is a link to additional information about pests of peony in the landscape:

 Please let us know if you have any additional questions regarding growing peonies in your area!

Contra Costa Master Gardener Help Desk

Note: The Contra Costa Master Gardener Help Desk is available year-round to answer your gardening questions.  Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA  94523. We can also be reached via telephone:  (925) 646-6586, email:, or on the web at

Posted on Monday, May 25, 2015 at 12:10 AM

Safety of GMOs debated online

Using genetic engineering, science has found a way to produce alfalfa with less lignin, a component of the plant that has no nutritional value.
A UC Agriculture and Natural Resources (UC ANR) genomics expert participated in an online debate about GMOs with a Canadian scientist who argued against the ubiquitous use of the technology. The debate can be viewed on The Real News.

Alison Van Eenennaam, UC ANR Cooperative Extension specialist in the Department of Animal Sciences at UC Davis, said research has shown that genetically engineered crops do not pose a risk to human health.

"There's a recent review paper where they summarized data from 1,700 different studies, and about half of those are publicly funded. And basically the results of those studies have been that there haven't been any unique risks or hazards associated with the use of this breeding method in the production of crops," she said.

The counter point was offered by Thierry Vrain, a soil biologist and genetic engineer with Agriculture Canada. He focused on the fact that more than 90 percent of the genetically engineered crops now in use were altered to be resistant to the herbicide glyphosate. He said this fact results in overuse of the herbicide.

"In terms of specific toxicity of the molecule glyphosate, which has very little acute toxicity - as it is advertised, it is safer than table salt. But in terms of chronic toxicity over time, over weeks and months, it will damage the microbiome and induce all kinds, all kinds of symptoms. In mice, and probably in humans," Vrain said.

Van Eenannaam tried to keep the discussion focused on the safety of GMOs.

"I think the most misunderstood thing is it's a breeding method that can be used to introduce all sorts of crop traits into crops and animals, and we always seem to get discussing the one particular application rather than looking at how it could be used to address many different problems that are associated with agriculture, including things like drought tolerance, disease resistance, biofortification of crops," she said.

Vrain agreed with most of Van Eenennaam's points.

"I agree with you, Alison, that GMOs are not necessarily toxic, et cetera, et cetera," he said. "There's all kinds of benefits, it's a very powerful technology. Used properly, it's probably very beneficial to humanity.

At the end of the debate Vrain reiterated his concern that the preponderance of GMOs are for glyphosate-resistant crops.

Posted on Friday, May 22, 2015 at 3:42 PM

Berkeley soda tax panel convenes

Berkeley's one-cent-per-ounce soda tax generated $116,000 its first month.
A nine-member panel of nutrition experts, including a long-time UC Agriculture and Natural Resources (UC ANR) nutrition specialist, convened for the first time this week to make recommendations to the Berkeley City Council about spending the funds raised by the city's soda tax, reported Emily Dugdale in NOSH.

"We're all in a fish bowl built out of a magnifying glass," a Berkeley City Councilmember told the panellists, referring to the national attention and strong community interest in the initiative.

Berkeley taxes sugar-sweetened beverages one cent per ounce. The tax generated $116,000 in its first month of operation.

The UC ANR panelist is Pat Crawford, the senior director of research for the Nutrition Policy Insititute, an organization of experts from throughout the University of California system brought together to share, synthesize, develop and collaborate on nutrition policy research.

In a recent Q&A with the UC Food Observer, Crawford commented on efforts to reduce consumption of sugar-sweetened beverages.

"We have strong evidence of sugar's contribution to diabetes, heart disease, obesity and dental caries," she said. "Hopefully educational materials for the public, including MyPlate, can begin to include water as the beverage that is first for thirst."

Posted on Wednesday, May 20, 2015 at 4:29 PM




By Linda Lewis Griffith    UCCE Master Gardener


Halloween may be the last thing on your mind. But it's not too early to get your pumpkins in the ground. Pumpkins come in a wide array of sizes, shapes and uses.  Tiny Jack-be-Littles fit in the palm of your hand and are perfect for toddlers or seasonal displays.  Big Max grows up to 135 pounds.  Cinderella Pumpkins are unique French heirlooms that were cultivated by the Pilgrims and served at the second Thanksgiving dinner. Luminas are a ghostly white color; they have a delicious flavor and are excellent for pies. Pumpkins grow best in fertile soil that has been enriched with well-rotted compost and manure.  Mound soil into small hills spaced 8 to 10 feet apart.    Plant 4 to 5 seeds per hill.  Thin to the 2 strongest plants when the seedlings are 3 inches high. Plants are spreading and vinelike with wiry, curly tendrils.  They can grow to more than 20 feet.  Their leaves are large and shaped like a maple leaf.

Pumpkins have separate male and female flowers on the same plant.  The male flowers don't produce fruit; they supply the pollen that fertilizes female flowers.  Pollen must be transferred to the female flowers by bees for fruit to develop. Male flowers develop first and can be identified by their long slender stems. Female flowers have a very short stem and miniature fruit at the base of the flower.

Soil should be free from weeds and kept moist throughout the growing season. Avoid getting water on the leaves as it may lead to powdery mildew. You can monogram a pumpkin by scratching a name into the fruit before the shell is hardened (usually in late August or early September).  The inscription will callus over and become more obvious as the fruit matures. 

Pumpkins are ready for harvest in approximately 100 days.  Smaller varieties mature slightly earlier.  Larger ones may take up to 120 days. 

 Cut pumpkins from the vines carefully, leaving 3 or 4 inches of the stem attached; pumpkins without stems  may not keep as well. 




Posted on Tuesday, May 19, 2015 at 7:07 PM
  • Author: Linda Lewis Griffith
  • Editor: Noni Todd

Daily Life For Master Gardeners

Asian Longhorned Beetle

By Andrea Peck


Out west, we have drought, but on the east coast, there is this giant beetle. I guess, giant is probably an overstatement, but the female does grow to 1.5” in length and that's before she puts on her antennae. The Asian longhorned beetle is native to China and Korea. As bugs often will, it found its way to America. Probably, the Founding Father Bug was a stowaway inside a box of inexpensive children's toys. The beetle is black and white and polished to a high sheen, not unlike a small child's toy. Actually, a little rugged child would probably be more interested in this live plaything than a toy. Of course, the parents of that rapscallion likely disposed of Mr. Original Beetle in their compost—only a bug's jump away from the backyard maple tree.

The reason this dressed-up beetle is newsworthy is because it has an insidious propensity for hole-boring. The beetle begins its descent into the tree through the bark, deep into the wood and finally rests inside the center or hardwood. It loves the maple tree, but will settle for a whole host of others, such as elm, willow, mountain ash, birch, poplar, katsura, mimosa, hackberry, London plane tree and horse chestnut. You can imagine how Mr. Shiny Pants is breaking down the maple syrup industry. According to a Youtube video I watched, the dime-sized holes can fit your average pen – they are that large, and dare I say, handy.

Unfortunately, trees with holes eventually become structurally unsound. If there is someone in the forest, the tree falls with a loud bang. If no one is there, it still falls.

The USDA is quite concerned. According to their estimation, 30% (1.2 billion trees) of the trees in the U.S. could be lost if this creature is not corralled. Because the bug hides deep within the confines of the tree, eradication can be difficult. This great thing about this beetle –for the beetle, that is—is that it can fly. In fact, when it is searching for a new host, it is capable of flying over 3,000 feet (1000 meters).  Beetles in search of a new home sometimes hitch a ride in infested packing material and firewood. Yet, one more reason not to move firewood! Currently, three states, Massachusetts, New York and Ohio are actively fighting the bug, while surrounding states are considered high risk. According to the USDA, the entire U.S. is susceptible to invasion.

We are pretty far away from the hullaballoo, but if you see a spiffy-looking beetle, let the authorities know.

The Asian longhorned beetle travels, after all.


Posted on Tuesday, May 19, 2015 at 7:00 PM

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