AboutC.L. Fornari Expertise Annuals suggested for specific situations (sun, shade, windowboxes etc) New or unusual annuals are a particular interest of mine, and I grow many of these from seed. I am happy to help problem solve, answer questions about maintenance, and guide you to sources of unusual plants.
Experience I am a garden writer/speaker/consultant and host of a weekly gardening radio program in the Northeast. I have been gardening all my life for my own pleasure, and started as a professional gardener and garden communicator 15 years ago. I work part-time at a garden center, selling and tending shrubs/trees/annuals/perennials...and doing some propagation and design work. I often think that all these professional activities serve to put a somewhat legitimate framework around a serious case of plant-lust.
I live just north of Atlanta, GA and I have a question about my dahlias.
I purchased a couple of potted dahlias from Wal-Mart and initially, I transplanted them into a bigger pot. One day when I came home from work, I noticed the leaves on the larger plant were a little brown and crispy. I also noticed that the flower buds turn brown and die, never opening up.
Today, I decided to put them in the ground and when I did, I noticed on the lower leaves, my friends, the leaf miners, have been hard at work. I put down some Bayer Flower and Rose Care Fertilizer (with insecticide) to take care of that little problem, but why are the leaves turning brown and the buds dropping? I don't over water them (I've learned that lesson the hard way over the years) and originally, they received morning sun for at least 5 hours. Where they're now planted, they should receive at least 6 to 8 hours of full sunlight.
So Far, it has been a wet spring/summer with the forecast of scattered showers another 3 days this week--could this be the culprit?
Thanks in advance for your help.
ChiTownDivaus
Answer ChiTownDivaus,
Brown buds and leaves can be caused by any of the following, or a combination of the below:
1. Fertilizer burn. If the plant has too much fertilizer it will "burn" the leaves, browning the newest foliage and buds first. This is likely to happen if a plant has been fertilized with a synthetic fertilizer (liquid, granular or time-release) when it is dry, or anytime fertilizer is applied at too high a concentration.
2. The plant goes too dry in-between waterings. When the roots get too dry in between times when the plant is well watered, the foliage and buds turn brown.
3. Fungal problems: if the weather is wet and cool, and foliage and buds are constantly damp, fungi can cause either leaf spot or browning of buds. Fungi are unlikely to cause an entire leaf to brown, however....usually just spots of the leaf.
From now on I'd do the following: no more fertilizer for awhile, including the Bayer product. Water deeply less often: when you do water, use a soaker hose or sprinkler and leave it on for at least an hour and a half - so that the soil is deeply soaked and then you can wait for another four to six days to water again. Spray the foliage with Serenade if you think fungus is the problem. Serenade is an organic fungicide (red bottles, available at garden centers) that helps get rid of "the bad guys".
