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How to keep petunias from becoming bedraggled
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August 31, 2005
CORVALLIS - Do your petunias look worn out, long or straggly by the end of the summer? To keep your petunia plants bushy and producing an abundance of blooms until the frost, follow this advice from Oregon State University Extension Service horticulturist Barb Fick.
Pinch back each stem to about 4 inches above ground after the first bloom. In a couple weeks, you'll have plenty of blooms again.
Keep the blossoms dry. Petunia flowers don't "like" to be wet. After a rain, the flowers will often close up and take several days to open again. To keep the flowers dry and open, use a soaker hose that slowly oozes water into the soil rather than an overhead sprinkler when watering.
Give your petunias an early summer and mid-season dose of fertilizer for blooming plants, higher in phosphorus than nitrogen.
Be careful not to plant disease carrying types of plants near your petunias. Aphids carry cucumber mosaic virus from infected cucumber plants to petunias. Plant disease-resistant cucumbers in the vegetable garden.
Keep tobacco products out of the garden. Tobacco mosaic virus can be spread to petunias when tobacco users handle the plants. Both these diseases cause petunia leaves to turn a mottled yellow-green and become deformed. Blossoms are also deformed. If you smoke or chew tobacco, wash your hands before working in the petunias.
Choose hearty, long-blooming varieties. In the last few years, there have been some new offerings in the world of petunias. The new Wave series petunias are incredibly popular and easy to care for. They are loaded with bright blooms, smaller than most other petunia varieties. They quickly spread to fill an empty space and are great in hanging baskets, containers and in window boxes. Varieties of Wave include: Rose Wave, Misty Lilac Wave, Pink Wave and Purple Wave.
Calibrachoas or 'Million Bells' are close cousins to the petunia. With smaller blossoms than the petunia, Calibrachoa is also a wonderful choice for summer hanging pots, containers and window boxes. They come in many brilliant colors.
Deadheading, or pinching off spent blooms is not as important with the Wave series petunias or Calibrachoas. They'll keep blooming like mad whether you remove the spent blossoms or not.
Source: Barb Fick