Perennial flowers like Siberian irises may already hold a special place in your gardens and landscape. But there's another flower in the iris family that you might consider adding for its color and movement, especially if you've got some soggy spots in your yard. It's the Japanese iris.
The perennial Japanese iris, or Iris ensata, blooms later in the season, in June or early July, after the Siberian irises and other flowering perennials have come and gone.
These impressive irises are tall, growing over 30 inches high with strap-shaped leaves. Their long, flat flowers bloom in a range of hues — white, pink, lavender and purple. And the petals can also have distinct and contrasting veining. The real show occurs when the summer breezes blow, and the petals' movement almost resembles the fluttering wings of butterflies.
Japanese irises are hardy to zone 4 and don't mind wetter soil in the spring. If you have areas in your lawn that tend to stay wetter, or if you have space streamside or near a pond, these irises will flourish.
Varieties like "Silverband" grow in lavender and purple colors, while "Great White Heron" has flowy, white blooms with a flash of yellow in the center. And a newer variety, called "Pinkerton," is a soft pink with a darker pink veining.
When planting Japanese irises, resist placing them too deeply into the soil — about 3 inches will do. And choose either a full sun or partial sun location in well-drained soil. These irises can take some extra moisture, but the soil shouldn't be soggy.
They're rhizomatous, and will spread via underground rhizomes, but not aggressively like some perennials. Add these to your landscape and you'll get to enjoy Japanese iris consistently year after year.
Will this weed killer also harm other things?
Q: I have recently become aware of a seed germination inhibitor called, Preen. I live within a few hundred yards of a lake so all water flows from here to there. I am wondering if this is a safe product to use in either the vegetable or perennial gardens. - Susan, in Castleton
A: You are keen to wonder about Preen. That's the brand name for a pre-emergent herbicide that kills weed seeds as they try to germinate.
The product is very toxic to amphibians and fish, so it should not be used near any kind of waterway, stream or lake.
Is late-budding rose of Sharon OK?
Q: My Rose of Sharon doesn’t have buds on it yet. Should I be worried? My autumn joy is coming up in the same flower bed that faces west. I have tried bee balm, hydrangea, and potentilla but they died after the first season. - Robin, in Willsboro, NY
A: With all the world's worries, rest assured that your late-budding rose of Sharon hibiscus needn't be one of them! If it's been growing in that same location and faring well, just give it a bit more time.
That is a shrub that tends to leaf out later in May, or even June, depending on your location in our region. The shrub might even look dead, but soon enough, its leaves will unfurl and buds will burst out. By August or September, you should have beautiful flowers blooming on it.
As long as the soil is fairly well-drained, your rose of Sharon (and the other perennials you mentioned) should be blooming and growing right on schedule.
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