I got a call last week from a reader who wanted to know if she should prune her butterfly bush now, before winter sets in.

No, you want to wait until spring, after new growth begins to appear on the lower branches. Then you can cut it back hard, to about 12 to 18 inches from the ground.

Here’s a link to a springtime post with more specific directions — and photos.

From an email newsletter:

“Leslie Day: The Field Guide to the Natural World of New York City

Thursday, December 4, 2008

The Arsenal
830 Fifth Avenue at 64th Street
6:00-8:00 p.m.

Third Floor Gallery

Light refreshments will be served

Author’s Workshop & Book Signing – Leslie Day, naturalist and author of the Field Guide to the Natural World of New York City will give an overview on the importance and the uniqueness of New York City’s urban environment. Join us and learn about the hidden natural wonders that are a part of the largest city in the United States.

Please RSVP at 212-227-1887 or info@treesny.com.”

Perennials: Wait until the ground freezes to mulch the garden. Continue to plant bulbs during mild weather. A thin cover of leaves over the bulb planting areas will discourage squirrels from digging up newly planted bulbs.

Flowers: Cut flowers will last longer if fresh diagonal cuts are made under water. Commercial preservatives also will extend the life of a beautiful bouquet. The florists use wet Oasis, a block of porous material, which holds flower stems securely. Read more of this entry »

Oops, I’m told that radio show on careers in horticulture was last Sunday. Sorry about that.

Dec. 5
Congers: Rockland Audubon Monthly Program. Speaker: Manna Jo Greene. Topic: Diminishing fish populations, development along the river and its impact on wildlife and ecology. Free. 8 p.m. Rockland Country Day School, 34 Kings Highway. 845-639-9216.

Dec. 6
New City: Hands-on topiary design workshop, led by a Cornell Cooperative agent. Registration by Dec. 3. $28 materials fee. 1:30 p.m. 845-634-4997, ext. 139.

Dec. 9
Stony Point: Holiday Wreath and Topiary Workshop. Bring a pair of pruning snips or shears and gloves. Registration. $25. 7 p.m. Cornell Cooperative Extension of Rockland County, 10 Patriot Hills Drive. 845-429-7085. Read more of this entry »

From Dachell McSween, Publicity Coordinator, The New York Botanical Garden:

“Careers in Horticulture will be discussed on WOR News Talk Radio 710 this Sunday at 9:05 a.m.

“Jeff Downing, Vice President for Education at The New York Botanical Garden, will appear on Ralph Snodsmith’s “The Garden Hotline” Show, to discuss career opportunities in Horticulture and Landscape Design. Read more of this entry »

I’ve got lots of old, dead trees and thick bramble. I often say a chainsaw is my favorite garden tool. We also try to cut our own wood to keep a wood stove and fireplace going all winter. I’m crazy about my 16-inch chainsaw from Husqvarna.

Here’s email from Brad Gurr, a certified arborist with SavATree in Ossining about how to go about picking one:

“Chainsaw Choices

“Professional chainsaw users know just how dangerous these valuable tools can be.

“Unfortunately too many professionals have learned the hard way that any time you are close to a chainsaw you are at risk of injury. The typical chainsaw combines the brute strength of 3 horses with seventy five razor sharp teeth. All this dangerous potential is literally in your hands when you pick up a chainsaw. Before you pick up a chainsaw you should make sure you have the right saw for the job. Read more of this entry »

Down to Earth nursery in Pomona goes all-out for the holidays every year. Here’s a link to my colleague Mary Shustack’s Just Browsing blog with all the details.

The last time I drove by they were having a huge sale on all their trees and shrubs.

And here’s info from the November newsletter on the annual Open House at neighboring Matterhorn Nursery, also in Pomona:

“The Holiday Season at Matterhorn officially begins with our Holiday Open House on December 6. Join us for a delightful day of wine, cheese, and holiday cheer! Our picturesque village is transformed into a winter wonderland with gifts for everyone on your holiday list. Matterhorn Grown Poinsettias are ready, and we invite you to select your favorites directly from the greenhouses. Savor the season at Matterhorn. Please visit our website for more information.”

For more on Down to Earth, go here.

Ask the master gardeners

Q: Why is “softened” water not good for plants?

A: Water softeners remove minerals, mostly calcium and magnesium, that cause water to be deemed “hard.” When water is hard, a myriad of difficulties can arise for a homeowner such as the occurrence of excess lime deposits and the frustration of soap not dissolving properly or at all. Therefore a water softener can be beneficial to everyday life for the homeowner. Most water softeners are briny, that is they contain salt such as sodium or potassium chloride.

Plants depend on a fragile mechanism called osmosis to survive. What happens in osmosis is that water passes by diffusion from a weak solution (high water concentration) to a strong solution (low water concentration) until an equality is reached between the two. In the case of a plant, the water from the soil (weak) into the plant roots (strong) provides the plant with the moisture it needs to survive.

When water that has been softened is discharged into the garden, the brine from the softener can alter the osmotic pressure that plants rely upon to regulate their water needs. This imbalance should be avoided.
— Judie Phillips, New Rochelle , master gardener, Cornell Cooperative Extension of Westchester

It’s not too late to plant spring-blooming bulbs — I planted a couple of dozen crocuses that I forgot I had just last weekend. As long as the ground is not frozen and you can get a shovel in, you can still plant bulbs.

One of the earliest bloomers in spring is a charming little variety known as ‘Tricolor.’ It’s extremely hardy and will actually bloom amid lingering snow on the ground.

‘Tricolor’ offers three distinct bands of color: bright orange in the center of each flower, then a broad band of white and a rich pastel purple edge at the tips of the petals.

(Photo from White Flower Farm)