If you’ve spent a lot of time working on developing the annuals and perennials in your garden, you’re worried most about two things – drought and disease. We covered ways to prepare for drought last week, so now we’ll take a look at some of the diseases that might hit your flower gardens and what, if anything, you can do to protect your flowers from disease.
This disease attacks impatiens, which are inexpensive and popular annuals. That doesn’t mean you’re okay with those plants catching a disease and dying, and ruining your garden. Downy mildew tends to attack the areas of the leaf veins, and can be contained to a single area by these veins. It grows inside of the leaf, producing spores that are detected on the surface. It displays as yellow spots, turning brown, and will most often appear on the underside of leaves.
Just because downy mildew and powdery mildew sound similar, does not mean the diseases are the same, nor does it mean the diseases can be treated the same. You need to make sure to properly identify which disease is attacking your plants before you try and treat it. Powdery mildew shows up as a white powder and only begins to cause the leaf to yellow after a long period, whereas the downy mildew is usually brown and causes immediate yellowing. Powdery mildew shows up in circular patterns, and will develop over the veins of a leaf.
A fungus that is most often seen on rose plants, it’s name is descriptive of what it is – black spots that appear on leaves, and sometimes the canes of the plant. These are caused by wet conditions and moisture sitting on the leaves for seven or more hours at a time. Temperatures above 85 degrees Fahrenheit will cause the spots to stop developing, but below that, they can grow up to 1/2 inch in diameter. There are a number of plants that have developed a resistance to black spot, so consider those when you’re planting.
Like the rest of them, this disease is appropriately named – it manifests itself as a gray mold. It’s also the most common disease to strike flowers. This will cultivate in areas soaked with water, particularly when plants are bunched together and there is overlap from one plant and group of leaves to the other. It tends to go after old and dying plants, so trimming off dead and dying matter and removing them from the garden will keep gray mold from gaining a foothold.
All of these diseases have fairly common causes, so prevention of the diseases all have a common thread-
- Prevent these diseases by concentrating watering at the base of the flower, keeping water off of the leaves and stems.
- Prevent these diseases by giving your plants space and not cording them together – these diseases grow in cool, dam places, so removing those cool, damp places will keep the diseases away.
- Remove the diseased leaves and areas of the plant to prevent it from spreading throughout the plant or to other, nearby plants.
- Spray the plants with beneficial bacteria such as that found in products like Serenade Garden Disease Control, which will attack the mold.
- Select disease-resistant varieties for planting.
Of course, these aren’t all of the diseases that can strike flowers, but merely some of the most common. Every flower has particular diseases that will target them, so consider that when planting as well as when you see diseases attacking. You may need to look for specifics by plant to make sure you are finding and targeting the right diseases for cure.