Divide irises after they bloom

Our bearded irises are coming up and they’re pretty crowded this year, and need to be dug up and divided. If we divide them now, before they bloom, will we still have flowers this year?

If your iris bed is crowded but still producing blooms, it is best to wait until later to dig up the iris bed and divide the rhizomes. The experts at the American Iris Society and other sources say iris beds should be divided every three to five years, and suggest mid- to late-summer as the best time for this task.

When the time comes this summer, here is the method suggested by author Judy Lowe in Month-by-Month Gardening in Tennessee & Kentucky:

Cut the leaves in a fan shape about 6 inches tall, then lift the clump with a spading fork, wash off the dirt, and inspect the rhizome for soft spots, damage or disease.

Cut the rhizome into smaller pieces with a sharp knife, making sure each piece includes an eye or a bud. Cut away any older growth. Lowe notes that iris rhizomes are susceptible to fungal problems, and suggests dipping the rhizome briefly into a solution of one part liquid bleach to nine parts water.

Replant the sections: Dig a hole and make a mound of soil in the center, then place the rhizome on top so that its roots spread over the mound. Cover the roots, but maintain the rhizome at soil level or just below it. Bearded iris rhizomes that are planted too deep may rot, she says. Water the bed well.

Dividing in summer allows the rhizomes to become established before the end of the growing season, and more likely to bloom well next spring.

Color Garden book giveaway

Thanks to readers who left comments this week for a chance to win The Nonstop Color Garden by Nellie Neal. Constance is the winner of the random drawing.

Nellie, her book, and information from Doris Weakley of the Perennial Plant Society of Middle Tennessee were featured in a story in last Saturday’s Tennessean. You can read it here.

And watch for another book giveaway soon.

Daffodils may be too crowded to bloom

Our bed of daffodils has been growing for many years and has a lot of thick foliage, but just a few blooms. They should probably be divided. Can I dig them up and replant them now? 

Daffodil bulbs divide themselves every year or two, and the clumps begin to compete for food and space. This will affect their blooming – they’ll begin to produce fewer and fewer flowers.
So, indeed, after bulbs have been growing in the same place for many years, they may need to be dug up and divided. When the foliage turns yellow later this spring (but before it disappears completely), dig the bulbs, separate them, and replant them about 6 inches apart, 6 inches deep.
This is prime-time for daffodils in Middle Tennessee, and a little extra care and attention this time of year can improve your daffodil planting over time.

–
April in the garden: This could be the start of an especially satisfying – or challenging – spring. Check out the April Garden Calendar in The Tennessean and at Tennessean.com.

–
A wise gardener once said…
In fact, there have been many wise gardeners, and they’ve said plenty of wise things.
“To sit in the shade on a fine day, and look upon verdure, is the most perfect refreshment.” (Jane Austen, in her novel Mansfield Park)
Author Barbara Burn has collected many such bits of truth in The Little Green Book of Gardening Wisdom, just out this spring from Skyhorse Publishing. If you keep a garden, it’s a book that’s likely to have you nodding in agreement as you flip through the chapters.
“I love spring anywhere, but if I could choose I would always greet it in a garden. – Ruth Stout, “How to Have a Green Thumb Without An Aching Back” (1955).
Burns says in the introduction that she was surprised to discover that so many people have said so many things about gardening that deserve to be collected. “I concluded that the subject of growing things was of far more universal interest that I had anticipated, and a great deal more uplifting than all the volumes devoted to war and political history,” she writes.
“To create a garden is to search for a better world. In our effort to improve on nature, we are guided by a vision of paradise. Whether the result is a horticultural masterpiece or only a modest vegetable patch, it is based on the expectation of a glorious future. This hope for the future is at the heart of all gardening.” – Marina Schinz, in Visions of Paradise (1985).
There is also practical advice, in quotes from well-known gardeners past and present.
“I feel that one of the secrets of good gardening in always to remove, ruthlessly, any plant one doesn’t like… Scrap what does not satisfy and replace it by something that will.” – Vita Sackville-West’s Garden Book (1968).
“To get the best results you must talk to your vegetables.” – Prince Charles, in a television interview in 1986.
This book of wise words is not intended to use as a how-to-garden manual. “But it will, I hope, give every reader a sense of comfort to know that we are not alone when we are down on our hands and knees fighting with weeds or planting a row of seeds that will one day bring us great pleasure.”
The Little Green Book of Gardening Wisdom is available at Skyhorse Publishing in hardcover ($16.95) and as an ebook.

Cannas multiply, time to divide

Question: I planted cannas several years ago and they have multiplied. I’d like to move some of them to a different location. When is the best time to transplant them?

In the University of Tennessee Extension Master Gardener Handbook, cannas are listed among the “tender bulbs and bulblike plants” along with caladiums, dahlias and gladiolus. At one time, it was recommended that these tubers be dug up and stored to protect them from the cold, but most gardeners in Middle Tennessee (Zone 7a) now find that they make it through winter just fine, especially if they spend winter under a blanket of mulch.

If you want to move them, an opportunity for doing so is coming up. According to the handbook, cannas can be dug in the fall after the foliage has been killed by frost. Allow the tubers to dry for a couple of days, then store them in a cool location (50 degrees or so – a garage or basement, perhaps) where they won’t dry out completely. The Old Farmer’s Almanac suggests storing them in peat moss or wrapping them in newspaper, and sprinkling them with a bit of water every now and then during the winter. Next spring, plant the tubers in a sunny spot when the soil has warmed to 65 degrees.

You may also wait until spring to divide the tubers. Mark their location now, and in the spring, use a garden fork to dig carefully and lift the tubers from the ground. Separate them, cut off any rotten or diseased bits, and replant them. Cannas do best in a location where they receive full sun.