July 2013

Popular fountain grass earns weed of the month moniker

Hameln fountain grass with Russian sage in the background. Photo courtesy

A popular ornamental grass planted in thousands of Indiana landscapes was named Purdue University’s Weed of the Month in June.

Fountain grass (Pennisetum) has escaped our garden beds and spread to the lawn, say Purdue turf specialists. ‘Hameln’ and ‘Little Bunny’ are two popular cultivars.

After years of planting in the landscape, “we now realize that this species produces many viable seeds that drop onto the adjacent turf and then become tough-to-control perennial grassy weeds. Although most of the ornamental grasses cannot withstand short mowing, fountain grass does,” the professors wrote in the Weed of the Month bulletin.

Fountain grass’ ability to withstand being mowed shows up as ragged, tan blades in the lawn, making it easy to spot. Even sharp mower blades cannot make a clean cut on this plant.

Native to Africa, Asia and Australia, pennisetums are prized for their fountain form, foxtail-like plumes, multiple seasons of interest and compact size.

The annual, red fountain grass (P. setaceum ‘Rubrum’), a staple in summer containers, is not considered a problem here because neither the plant or the seed are apt to survivewinter. Howeverin warmer climates, it is an invasive weed.

The perennial fountain grass (P. alopecuroides) has spread into natural areas, called naturalizing, in New York, Pennsylvania, Illinois and Arkansas. The National Park Service’s National Capital Region Exotic Plant Management Team has issued an alert on the perennial species, identifying it “as a potential or emerging threat to natural areas in the mid-Atlantic region.”

Prairie dropseed and purple coneflower are planted together in downtown Chicago's Lurie Gardens (C) Photo courtesy Lurie Gardens

Although perennial fountain grass is not on Indiana’s invasive species list, some gardeners may want to plant alternatives if only to keep pennisetum from spreading into the lawn.

At the top of my list would be prairie dropseed (Sporobolus heterolepis). This 3 feet tall and wide native grass has a fountain form, frothy flowers and turns a beautiful golden orange/red in fall. It does not freely self sow.

Prairie dropseed flower. Photo courtesy of

Prairie dropseed. Photo courtesy

Pink Zazzle gomphrena dazzles

Pink Zazzle gomphrena. (C) Jo Ellen Meyers Sharp

I’m just back from the country’s largest horticulture trade show in Columbus, Ohio, and am full of plant lust.

In the annual category, the showstopper this year was the sun-loving Pink Zazzle (Gomphrena), which at first glance looks like a dahlia, mum or perhaps a Stokes’ aster (Stokesia).

Pink Zazzle gets up to 16 inches tall and has some of the fuzziest leaves you’ll find on any plant. The flowers are about 3 inches wide and reportedly hold their form well.

Pink Zazzle gomphrena has gold flecks at the tops of petals.. (C) Jo Ellen Meyers Sharp

The tips of the petals have just a hint of gold. The long-lasting flowers turn to a soft pink as they age and develop creamy petal tips. Like all gomphrenas, Pink Zazzle, from Euro American/Proven Winners, has long enough stems to use as a cut flower.

This will probably be a premium annual, available in the next couple of years in individual pots, rather than as a bedding plant. I can hardly wait to try it.

Always the fashion plate in its marketing schemes, Hort Couture’s Glamouflage Grape petunia shows promise. This sun-loving annual will get about 8 inches tall with a 12 inch spread, making it ideal for containers or in the ground.


Glamouflage Grape petunia from Hort Couture. (C) Jo Ellen Meyers Sharp

The flowers are various tones of purple with dark veins and a touch of white throat. The flowers pop against variegated green and cream foliage.

Babuda Yellow marigold. (C) Jo Ellen Meyers Sharp

Marigolds are making a strong come back, primarily as a bedding plant, if the trial gardens at Ohio State University are an indication. These annuals add a bit of cheer in sunny locations.

Those in the trial garden were very clean — no signs of spider mites, a plague on marigolds — and the flowers were much larger that what we’re used to seeing. And even though the flowers are larger, the plants held their shape nicely. Some of the best marigolds (Tagetes) in the trial gardens were in the Alumia and Babuda series.


Rain pushes growth and roots struggle to keep up

A branch of ‘Limelight’ hydrangea (H. paniculata) grew about 7 inches and exhibits a bit of chlorosis. © Jo Ellen Meyers Sharp

Compared to last year, when crispy and brown defined the landscape, this year’s weather has created a lush, tropical jungle.

Trees, shrubs, perennials and vegetables have been growing rapidly. Aphids love this fresh new growth. They are slow moving insects that take on the color of the plant they are eating, such as brown, green, red, yellow or white.

Aphids suck the juices out of flowers, leaves and their buds, stunting them or causing them to be malformed. A strong spray of the hose will knock aphids off plants.

Some plants may have a yellow cast to them or their leaves are chlorotic, where the veins are greenbut the tissue between them is yellow or mottled. This could be from all of the rain washing nitrogen from the soil. Or it could be the plant’s roots trying to catch up with all of the rain.

The fine, hair-like roots on trees and shrubs seek out water. However, these roots have likely taken a hit from the last three years of low rainfall and droughtand they are trying to catch up. Or it could be the pH of the soil. Too alkaline or too acidic, and plants may not be able to take up nutrients.

The first step to learn what’s going on is to get a soil test. Purdue University has a good publication to tell you how.

Hot weather precautions

When gardening in hot weather, be sure to drink lots of water and protect yourself from sunburn and bug bites. © Jeff Wasserman/Dreamstime

When the weather is hot and humid, gardeners need to make sure they are not overcome by the heat. Here are some tips:

  • Drink lots of water before, during and after working in the garden.
  • Work outdoors in early morning and evening.
  • Wear loose fitting clothing and a hat. Use sunscreen and bug repellent.
  • Work in pairs for big jobs, such as tree or shrub removal or creating a new garden bed.



Blueberry harvest just sweet enough

Northsky lueberry harvest. (C) Jo Ellen Meyers Sharp

Ok, the blueberry harvest did not fill a bushel, but it did provide just enough of the sweet fruit in a green salad for a family dinner.

This is year three of ‘Northsky’ and it’s the first real harvest. I bought this plant four falls ago just because of the gorgeous, red leaves. The fact that it might produce blueberries was sort of a bonus.

BrazelBerries Jelly Bean blueberry. Photo courtesy BrazelBerries

Consumer interest in the anti-oxidant fruit powerhouse is high  and the breeders have responded with dwarf plants and those that are self-pollinating.

The dwarf ‘Northsky’ (Vaccinium) gets up to 3 ½ feet tall and 3 feet wide. Mine grows in a 20-inch wide and deep all-weather container. By growing it in a container, I’m able to control the soil  environment the blueberry needs to survive and thrive. That means regular doses of Espoma’s Holly-Tone, an acidic fertilizer. Blueberry plants require an acidic soil in order be able to take up the nutrients they need to survive.

BrazelBerries Peach Sorbet blueberry. Photo courtesy of Brazelberries

Last summer and this spring I was vigilant about fertilizing the shrub. Too late for this spring, I learned the plant should be pruned to encourage better fruit production along main branches.

‘Northsky’ produces the most fruit when it has a companion, such as ‘Northblue’ or ‘Northcountry’.

Last year I added three more dwarf blueberries to trial from BrazelBerries: two Peach Sorbet and one Jelly Bean. The new blueberries are bred to be grown in containers and are self-pollinating, but there was no fruit this year. I think it’s because they were tiny when I planted them last fall. Peach Sorbet gets its name because of the foliage color in  fall. It gets 2 to 3 feet tall and wide. Jelly Bean is even smaller at 1 to 2 feet tall and wide.

Although there was no fruit, these new blueberries are growing well. And, as most gardeners say, it will be better next year.



You Can Grow That! July 2013: Fireworks in the garden

Fireworks mix allium is planted in fall.

If you’re looking to spark up the landscape, consider some plants with fireworks.

‘Fireworks’ (Pennesetum setaceum rubrum) is a variegated fountain grass that is a great substitute to the popular plain red one. This annual ornamental grass is not winter hardy in Indiana, but it is beautiful all summer and into fall.

‘Fireworks’ grass gets about 30 inches tall and has a spread of 24 inches. In mid-summer, wispy, purple tassels bloom above leaves with pink, creamy white, green and burgundy stripes.

Use as a center piece in a container or as a specimen plant in the landscape. Plant in full sun. It was developed by ItSaul Plants, which also introduced the popular Big Sky series of coneflowers (Echinacea). Look for ‘Fireworks’ ornamental grass in garden centers.

‘Fireworks’ globe amaranth (Gomphrena) is an easy-to-grow annual from seed. Balls of hot pink flowers with gold-tipped petals top sturdy stems all summer long, making it an excellent cut flower.

'Fireworks' gomphrena has pink flowers tipped in gold sparks. (C) Jo Ellen Meyers Sharp

‘Fireworks’ globe amaranth gets 36 inches tall with a 12-inch spread. Use as the center piece in a container or as a showy mass planting in the landscape. Plant in full sun.

This globe amaranth may be a little hard to find at garden centers, but should be available through mail-order or online retailers. Introduced by Ball Horticulture, its sister company, Burpee, offers seeds and plants.

'Fireworks,' an annual ornamental grass, sparks up the landscape in summer. Photo courtesy

Allium Fireworks mix is a collection of three perennial ornamental onions. Clusters of fragrant rose, yellow or white flowers bloom in summer, giving the impression of fireworks. They get  about 12 inches tall and can be cut for indoor arrangements.

Grow in full sun in the front of the perennial garden. Winter hardy alliums are planted in fall, so look for this mix in bulb catalogs.

HortusScope for July 2013

Here’s HortusScope for July 2013, a checklist of garden and nature related events compiled as a public service by Wendy Ford of Landscape Fancies. Please click on the link below to download your copy.

HortusScope July 2013 (451) 



July garden checklist posted

A checklist of things to do in the garden in July has been posted under Gardening Checklist.