Bulbs have been on my mind all week. Last Friday I was in Keukenhof Gardens in the Netherlands, where about 5 million tulips and other bulbs provide breathtaking plantings over a 70-acre park.
This year’s theme: The Romance of Flowers. Five indoor pavilions provide education on tulip history and science as well as exciting plant introductions. If you love flowers, this is one place in the world to visit some April or May.
While there, I heard many times over: “We’re sorry that all the bulbs haven’t opened yet … Maybe one-third are yet to open. Spring is two or three weeks late this year.”
Then I came home to a similar story ...
Bulbs back home
A late spring is not a bad thing for most gardens, especially if the warm-up is steady rather than volatile. We are fortunate that the warm spells last month were very brief – not enough to trigger much plant growth or to cause woody plants to break dormancy.
Some bulbs began to pop up, at varying speeds depending upon the location of the garden. Some Buffalo friends have seen 7 or 8 inches of tulip or daffodil stems and leaves, while at my East Aurora house most are still just 4 inches tall. That is, I think that’s how tall they are under all the snow.
How late are they? I asked former extension agent and bulb expert Roxanne McCoy what was happening in her West Falls fields. Roxanne owns Lilies of the Field, where her family grows and harvests thousands of cut flowers (bulbs, annuals, and perennials) to sell at farmers markets, flower shops, or retail locations.
Tulips are the first crop she harvests. Normally she would be selling them on the first Saturday in May, when the East Aurora farmers market opens, for instance. But this year it’s tough to say how many will be ready at the Lilies of the Field booth. Like all farmers and growers, the McCoys will be watching the weather.
“Last year I was picking tulips this week, but now the same varieties are about 4 inches tall. I think we’re running about two weeks behind, average, and three weeks behind last year,” Roxanne told me.
What damage might occur?
I hear these questions wherever gardeners are gathering: “What will happen to my poor little bulbs? Can I do anything to help them?”
Usually we can rest easy in Western New York. Most hardy bulbs will be just fine because of their cellular structure. They have a kind of anti-freeze that prevents the cells from swelling, freezing and bursting when the temperatures drop. Most bulbs start to grow when heat and sunlight trigger them, and then they stall in place when a freeze comes.
Snowdrops, daffodils, crocuses, hyacinths and some tulips are among the many hardy bulb species.
Snow is no problem whatsoever (unless a heavy snow bank smashes the plants). Snow acts as an effective mulch, preventing extreme temperature fluctuations and heaving. In fact, a smart move if you see bulbs rising above the snow level: Add more snow! Gently push more snow over them; it will act as a blanket now and melt at the right time.
One situation puts plants at risk: Damage can result if your bulb plants, already emerged, face an extended period of temperatures (day and night) below 30 degrees, or the temperature drops suddenly into the teens.
High winds make it worse, drying out the plants severely. It’s called “dry wilt” – similar to winter desiccation of evergreens, when the plant loses moisture and is unable to replace it because the ground is frozen. The taller and farther along the plant, the more vulnerable it is to extended deep freezes, high winds, and desiccation.
What you can do
It’s not too late to help the situation in the face of the next serious freezing period. I mentioned using snow as a mulch. Or you might spread a lightweight organic mulch over the bulb bed – perhaps saved-up pine needles, chopped leaves, evergreen boughs or straw. You can also spread blankets, or cover the beds with thick newspaper – held down by sheets. Anchor the covers with rocks or stakes to prevent them from blowing away in the inevitable winds. Do not use plastic.
To protect tall stems and flowers use upside down buckets, yard furniture or stakes covered by tennis balls or flower pots to elevate the heavy covers. If you have a precious bulb display at risk, copy what some growers and bulb event planners do (as in the Tulip Time Festival in Holland, Mich.): If the plants are maturing too quickly and a deep freeze is threatened, spray the plants with water. The freezing layer will buffer them from the wind and then melt in the daytime.
It’s not easy to do. Your hoses are either put away or frozen, and lugging watering cans from the house is a chore – but it’s an answer for some.
Prevent the problem
• Early, middle, late bloomers: Especially narcissus and tulips offer a wide range of emergence times. If you crave early flowers, place those types in the most protected locations. I prefer shorter and later blooming varieties because the early and tall ones often get whacked by storms.
• Location: A protected spot on the eastern side of the house will save bulb plants from the wind and may offer a bit of reflected heat from the building. Plants on high ground are safer than plants at the bottom of a hill or bank since cold air accumulates and lingers in low spots. (Since tulips are especially tasty for deer, it’s wise to place them nearest the house, in containers, or behind barriers.)
• Mulch in fall: After the ground freezes over the bulb bed with about 4 inches of organic material. Avoid large leaves (oak, for instance) that mat and prevent rain from penetrating the soil. Then don’t remove the mulch in mid-spring just because you’ve seen the sunshine and some robins.
In cold climates, including ours, fall-planted bulbs provide wonderful spring flowers. Stop worrying and just watch!
* Read Sally Cunningham's column from last week.
Sally Cunningham is a garden writer, lecturer and consultant.