Rose and Ornamental Cherry Leaf Spot

Roses and most ornamental Cherry Trees need repeat fungicide applications to protect them from leaf spot disease. Our typical May showers create perfect conditions for disease development. Organic fungicides are Messenger, lime-sulfur (calcium polysulfide) and Neem oil. Three systemic fungicides are Propiconazole, Myclobutanil, and Tebuconazole. Propiconazole is available in Ferti-lome Systemic Fungicide. Myclobutanil is in Spectracide Immunex Fungicide. Tebuconazole is in Bayer All-in-One Rose and Flower Care and in Bayer Disease Control for Roses, Flowers and Shrubs. These 3 systemic fungicides stop disease development in already infected leaves as well as protecting new uninfected leaves. Daconil and Chlorothalonil are also widely available and effective, but are not systemic and therefore protect only new uninfected leaves. In most cases you will have to look at the list of ingredients to find the technical, chemical names. The Bayer products are applied to the soil as a drench and are not washed off by rain. Most need to be applied every two weeks to prevent disease infection. Three treatments should be enough for ornamental cherries. Roses should be treated throughout the spring and summer.

Plant Tender Flowers, Vegetables and Containers

We are now far enough past our average last frost date that we can plant just about anything. I usually wait until late May to plant my peppers because the cool night temperatures in early May stunt their growth. Nurseries and garden stores have their widest selection of flowers and vegetables this month.

Most of us have an area in our shrub beds where we can plant some annual or perennial flowers. If not, some grass can be removed in front of shrubs to create space. Check labels for sun and shade requirements. Most sun loving flowers need a minimum of 5 hours of direct sun per day to thrive.

About half of my hanging baskets are single varieties and half are mixed. In mixed baskets I tend to use just 2 or 3 different kinds. Most of my single variety baskets are one color. My favorite single variety mixed color combinations are white, pink, and deep rose, or white with light and dark blue. One of my favorite two variety combinations is Calibrachoa (Million Bells) with Bacopa.

Some of the best plants for single variety containers are ivy Geraniums, Impatiens, hanging basket Begonias, Fuchsias, Bacopa, Calibrachoa (Million Bells), Scaevola, and trailing Petunias. Not all Petunias are suitable for containers. Most bedding Petunias tend to grow upright and do not trail properly. Even the Cascade petunias do not trail properly for containers. The Wave and Supertunia series of petunias are great for containers.

Most of my tubs are mixed plantings. I like to plant at least 2 or 3 plants of each kind per container. I place like plants across from each other or at equal intervals around the container. I place plants so that their soil balls are almost touching each other to get a more immediate effect. There are no bad color combinations in containers. However, I usually avoid mixing red or orange with bright pink

I usually plant one to three upright growing plants in tubs and larger containers. . Some good upright plants are Osteospermum, Salvia, Dracaena spikes, Snapdragon, and ornamental grasses.

If containers are going to be placed under overhangs or other shady areas, choose shade tolerant varieties. Fuchsia, Impatiens, Begonia, Coleus, Pansy, Viola, Lamium, Browallia, Laguna Lobelia, Nierembergia, and variegated ivies grow well in the shade.

For sunny areas, some of the most popular flowers include Diascia, Petunia, Ivy Geranium, Laguna Lobelia, Brachycome, Bidens, Nemesia, Pansy, Bacopa, Calibrachoa (Million Bells), Alyssum, Trailing Snapdragon, Trailing Verbena, Lotus, and sweet potato vine.

Be bold and try different combinations of colors and plants. One of the nice things about containers is that plants are spaced close together. If one or two plants do not make it, the others will grow and fill in the space.

Lawn Mowing Height and Clippings

The leaves of all plants are where food is manufactured. Leaves absorb sunlight and combine carbon dioxide with water to create carbohydrates for growth and energy in a process called photosynthesis. More leaf area means healthier grass.

During cool spring weather lawns mowed short or long will grow well. It is during hot, dry, summer weather when longer mowing height will make a big difference. Research has shown that grass root depth is directly proportional to leaf blade length. The longer the grass, the deeper the roots. Deeper roots withstand drought better and can go longer between irrigations.

The general rule in mowing grass is to not remove more than 2/5ths or 40% of the leaf blade. If grass is mowed at a one inch height, it should be mowed when it reaches 1 ¾ inches. If mowed at 2 inches, it can wait until it reaches 3 ½ inches. So the longer you mow grass, the longer the interval between mowings. If you wait until the grass is 3 or 4 inches and then mow at 1 inch or less, the lawn is damaged. Golf course putting greens, which are mowed at a fraction of an inch, are mowed every day.

Because grass grows faster in May and June, it should be mowed more frequently than once a week. From July on, once a week mowing should be enough.

Another frequent question about lawn mowing is whether to remove clippings or let them fall between grass blades. More frequent mowing means shorter clippings, which fall between grass blades more easily. Accumulation of clippings on top of the lawn are unattractive. However, occasional clumps of clippings can be scattered by running the lawn mower over them again. Clippings also stick to shoes and pet feet and are tracked into the house. This is sometimes reason enough to pick them up.

Clippings break down into humus over several months. The humus is converted into compounds which are available as fertilizer. One year’s accumulation of clippings is equivalent to one fertilization. That is definitely beneficial to the lawn.

Prevent Worms in Apples and Pears

As soon as flower petals have all fallen, it is time to protect apples, and to a lesser extent pears, from codling moths. Codling moths lay their eggs on developing fruit. Eggs hatch into worms which bore into the fruit. Insecticides such as malathion and carbaryl (Sevin) kill the worms as they hatch. They need to be applied every two weeks until about August first.

Codling moth traps can be placed in trees to trap the male moths. They are attracted to the pheromone in the traps. If enough traps are placed in trees, virtually all the male moths are trapped. Without fertilization, the female moths lay infertile eggs. Large trees may need up to 5 traps. Three traps is normal for most semi-dwarf trees. If you have some large neighboring trees which do not have traps, your traps may not be completely effective.