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"What's New in Perennials"

It's always exciting to grow something new and different in the garden. There are many new perennials that have been introduced in recent years with nice attributes. All of them can be planted any time now through fall. Click on a plant name below to order it from Pernell Gerver's Online Store.

Stokesia 'Color Wheel' is an exciting new variety of Stokes' aster. If you're not familiar with Stokes' aster, it's a perennial with large, flat flowers that are several inches wide. The usual flower colors of Stokes' aster are shades of blue, cream, or yellow, but the variety 'Color Wheel' is a color breakthrough in Stokes' aster. Each flower opens pure white then goes through a color metamorphosis, fading to lavender and finally purple as the flower matures. Numerous flowers are held on many-branched stems and at any one time there are as many as five different flower colors on each stem, creating the "color wheel" effect. Flower stems reach two feet tall. It has strap-like leaves that form a clump about 10 inches high and a foot wide. It begins blooming in late May and continues blooming into mid summer. It's a very striking perennial that grows well in sun to part shade. In my garden, it's growing in a rather shady spot and it's thriving.

Coneflowers are popular summer-blooming perennials that are prized for their long-blooming flowers. Hybridizers have been doing lots of work with coneflowers creating new and exciting flower colors and flower shapes.

Coneflower 'Harvest Moon' is a brand new color in coneflowers. Each large, four-inch-wide flower has golden-yellow petals and a golden-brown cone. The flower color doesn't fade, even after it's been in bloom for a couple of weeks. In addition to its stunning flowers, this coneflower is also more compact, growing just two feet tall and wide. It's a well-branched plant, providing dozens of flowers from midsummer onward.

Another new coneflower being introduced named 'Razzmatazz' has flowers that don't look much like a coneflower at all. In fact, they look more like a dahlia or peony instead of a coneflower. The flower opens as a single flower, then develops a cluster of fringed, rose-pink center petals, giving the flower a pompon look. The flowers bloom from July to September on 30-inch stems.


Shasta daisy is a popular summer-blooming perennial and here again is another color breakthrough. Called 'Sonnenschein,' this new Shasta daisy bears creamy-yellow flowers instead of white. The flowers have a deep-golden-yellow center and are single, semi-double, and double, all on the same plant. The three- to four-inch-wide flowers bloom in midsummer on three-foot-tall flower stems.


Baptisia 'Twilite Prairieblues' is a new baptisia with stunning flowers. Tall spikes of violet-purple flowers with yellow undersides stand above attractive, blue-green foliage. It's a prolific bloomer - a mature plant can have up to 100 flower spikes in bloom at a time! It blooms in late spring and early summer and forms a handsome clump three feet high and wide.


Pernell Gerver's Gardening Q & Aby Pernell Gerver

"Neem Oil Controls Cucumber Beetle and Rust"

Q. My cucumber and bean plants started off fine, then the lower leaves began turning yellow, shriveling up, and dropping off, eventually affecting all the leaves and killing the plants. I was growing them in containers. What do you think was the problem? I assume it was some sort of disease, not a nutritional deficiency. Thanks.

A. Both cucumbers and beans are susceptible to several different diseases that exhibit the symptoms you describe. Yellowing leaves on cucumbers is usually caused by bacterial wilt. Bacterial wilt is spread by the striped or spotted cucumber beetle as it feeds on the leaves. The beetle, only about a quarter of an inch long, chews small holes in the leaves. The damage it does to the leaves is minimal, but the disease it transmits eventually kills the plant. There is no cure for bacterial wilt, but the cucumber beetle can be controlled with Neem Oil, an organic insecticide, fungicide, and miticide. I spray my cucumber plants with Neem Oil about once a week. What I found also helps is to drench the soil with Neem Oil because the larva of the cucumber beetle feed on the plants' roots.

Yellowing leaves on bean plants can be caused by rust, a fungal leaf disease. It begins as small, rust-colored spots on the undersides of the leaves. The upper surface of the leaves turns yellow, the leaf shrivels, and then drops off. When it's severe enough, it kills the entire plant. Rust can be controlled with Neem Oil. Spray every seven to 10 days to prevent it.

Since you've had these disease problems this year, I'd recommend discarding the soil in the containers and starting with sterile soil next year if you plan to grow these vegetables in containers again. I use a special blend of sterile, soilless potting mix in all my containers. Click here to read more about this General All-Purpose Potting Mix and order it from Pernell Gerver's Online Store.

Click here to read more about Neem Oil and order it from Pernell Gerver's Online Store.

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