Hormone imbalance and heat fluctuations linked to deformed flowers
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This About Face grandiflora rose is displaying
fasciation in its spent bloom. (Photo: Debbie
Arrington)
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They look like something out of “Little Shop of Horrors”: Weirdly distorted buds that sprout out of the center of a spent rose. And this summer, more seem to be popping up on rose bushes throughout Sacramento – as well as other plants.
It’s another garden oddity likely tied to extreme fluctuations in temperature: Fasciation.
This phenomenon – strange, unexpected growth of terminal buds – is a genetic mutation of a plant’s growing tip. It’s believed to be triggered by a hormone imbalance that may be caused by outside factors such as roller-coaster temperatures or exposure to herbicides (such as Roundup).
I can’t help it; I’m fascinated by fasciation. In roses, it looks like a whole spray of monstrous buds is trying to wiggle out of the center of a bloom – often before the first flower has dropped its petals.
I have one hybrid tea – Perfect Moment – that always seems to display some fasciation in the heat of summer (and it did). But this August, I’m also seeing fasciation on bushes that never showed it before. That includes About Face, a very tall grandiflora; this week, several of its spent blooms sprouted the weird deformed buds.
The roses were not exposed to Roundup or other chemicals; it had to be the heat.
The good news: It’s not contagious. Snip off the weird flower and the plant will (fingers crossed) grow a “normal” bud.
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Fasciation also can show up in sunflowers. This was a
bloom that exhibited some weird extra growth. (Photo: Kathy
Morrison)
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In strawberries, fasciation creates giant double or triple berries. The cockscomb celosia – with flowers that look like rooster heads – are a result of fasciation.
Heirloom tomatoes – particularly those with ugly bottoms – are believed to be another case of fasciation as a desirable trait.
Fasciation also can produce flat, fused stems or tufts of fused growth, often referred to as “witches’ broom.” Besides heat and herbicides, fasciation may be caused by bacteria, in particular Rhodococcus fascians , say UC master gardeners.
For more on fasciation: http://ipm.ucanr.edu/PMG/GARDEN/FLOWERS/DISEASE/fasciation.html
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Food in My Back Yard Series
July 1: How to grow summer salad greens
June 24: Weird stuff that's perfectly normal
June 17: Help pollinators help your garden
June 10: Battling early-season tomato pests
June 3: Make your own compost
May 27: Where are the bees when you need them?
May 20: How to help tomatoes thrive on hot days
May 13: Your plants can tell you more than any calendar can
May 6: Maintain soil moisture with mulch for garden success
April 29: What's (already) wrong with my tomato plants?
April 22: Should you stock up on fertilizer? (Yes!)
April 15: Grow culinary herbs in containers
April 8: When to plant summer vegetables
April 1: Don't be fooled by these garden myths
March 25: Fertilizer tips: How to 'feed' your vegetables for healthy growth
March 18: Time to give vegetable seedlings some more space
March 11: Ways to win the fight against weeds
March 4: Potatoes from the garden
Feb. 25: Plant a fruit tree now -- for later
Feb. 18: How to squeeze more food into less space
Feb. 11: When to plant? Consider staggering your transplants
Feb. 4: Starting in seed starting
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Garden Checklist for week of June 29
We're into our typical summer weather pattern now. Get chores, especially watering, done early in the morning while it's cool.
* It’s not too late to add a splash of color. Plant petunias, snapdragons, zinnias and marigolds.
* From seed, plant corn, pumpkins, radishes, winter squash and sunflowers. Plant Halloween pumpkins now.
* Keep your vegetable garden watered, mulched and weeded. Water before 8 a.m. to reduce the chance of fungal infection and to conserve moisture.
* Water, then fertilize vegetables and blooming annuals, perennials and shrubs to give them a boost. Feeding flowering plants every other week will extend their bloom.
* Don’t let tomato plants wilt or dry out completely. Give tomatoes a deep watering two to three times a week.
* Harvest vegetables promptly to encourage plants to produce more. Squash especially tends to grow rapidly in hot weather. Keep an eye on zucchini.
* Pinch back chrysanthemums for bushy plants and more flowers in September.
* Harvest tomatoes, squash, peppers and eggplant. Prompt picking will help keep plants producing.
* Remove spent flowers from roses, daylilies and other bloomers as they finish flowering.
* Pinch off blooms from basil so the plant will grow more leaves.
* Cut back lavender after flowering to promote a second bloom.
* Give vegetable plants bone meal or other fertilizers high in phosphate to stimulate more blooms and fruiting.