Monthly Archives: October 2018

Learn About Hardiness Zones

Garden Design

If you’ve spent any time on our website, or read any of our catalogs, you’ve likely encountered the term “hardiness zone.” We’d like to de-mystify this term a bit, and explain how location should play into your selection of plants.

What Is a Hardiness Zone?

Using historical temperature data, the US Department of Agriculture (USDA) has divided the country into 13 hardiness zones, ranging from 1 (coldest) to 13 (warmest). Each of these zones is further divided into “A” and “B” for greater accuracy, with A being colder than B. Click here to see the USDA’s hardiness zone map. These zones are defined by average annual minimum temperatures. For example, a zip code in which the average annual minimum temperature is between -15 and -10 Fahrenheit is assigned to hardiness zone 5B.

The idea behind the map is that a gardener may look up his or her hardiness zone and use it to identify plants that will thrive in their area. For example, a gardener in Northwest Connecticut (hardiness zone 5) may confidently plant a variety that has been rated hardy to zone 4 but would generally not plant a variety that is rated hardy only to zone 6, because the zone 6 plant is not likely to survive the typical winter in that area.

How To Find & Use Your Hardiness Zone on WhiteFlowerFarm.com

First, go to www.whiteflowerfarm.com. At the top of our home page, just under the Search box, click on Find Your Hardiness Zone and enter your zip code in the box that appears, then click on Look Up. When the page reappears, your zone number will be listed at the top of the page (in the spot previously occupied by Find Your Hardiness Zone). As you navigate our site, use the filters on the left side of the page to narrow down a listing to display only plants that will thrive in your zone.

If you choose a plant or plants that are not considered hardy in your zone, our site will offer a gentle warning at checkout. This is not intended to dissuade you (in fact, plants can sometimes be “pushed” to grow outside their hardiness zones), but we wish to help you avoid any possible disappointment if a plant fails to perform well due to a climate mismatch. Please be aware that we cannot honor our usual guarantee on plants that have been shipped outside of their suggested hardiness range.

Sometimes Hardiness Ratings Include “S” or “W” – What Does This Mean?

When listing the hardiness range of a plant, we often “split” the warm end of the range—for example, you might see a plant listed as Hardiness Zone: 3-8S/10W. In this instance, the 3 refers to the “cold hardiness” of the plant—all else equal, this variety should overwinter successfully in zone 3. The 8S refers to the humid Southeast (the ‘S’ being for ‘South’) and the 10W (‘W’ for ‘West’) to the comparatively dry Pacific Coast states of CA, OR, and WA—this plant can tolerate zone 8 temperatures in the South, and zone 10 temperatures on the West coast. In Northern climates, summer heat is not typically a consideration.

So to summarize—a plant listed as 3-8S/10W should successfully overwinter in zones 3 or warmer, tolerate humid heat up to zone 8, and tolerate dry heat up to zone 10.

We realize this is complicated; the problem is that the USDA zones are really not sufficiently specific. For example, our nursery in Connecticut is in the same hardiness zone as Taos, NM—a climate that could hardly be more different than ours. Furthermore, there are innumerable other variables that may determine how a plant fares in a given site. We find that customers, over time, gain a good understanding of which plants do and don’t work for them, and that this understanding is much more helpful than a strict reliance on hardiness zone. When in doubt, please contact us—our customer service team is extremely knowledgeable and ready to assist.

Different Types of Amaryllis

Garden Design

We start the holiday season with over 70 Amaryllis varieties, including Singles, Doubles, Nymphs, Small-Flowered Varieties and Cybisters in a dazzling range of colors. Our Amaryllis bulbs are the top size commercially available (larger than what is generally seen at retail stores) and have been fully prepared at the proper temperature. Given warm temperatures, strong light, and water upon arrival, they will put on a spectacular show that will brighten up even the gloomiest winter day. Scroll below to see the wide range of varieties and colors available.

The 5″ double red blossoms of Amaryllis Fanfare® are very flared, very full, and very ruffled.

South African Amaryllis produce the same large, richly colored blooms as their Dutch cousins, but on an earlier timetable. Because bulbs grown in the Southern Hemisphere mature sooner in the year, we begin filling orders in October, and South African varieties will bloom about 6-8 weeks from receipt, often in time for the holidays.

Cybister Amaryllis produce delicate blooms that look more like wildflowers or dragonflies. These reliable growers will delight you with their colorful yet exotic flowers.

The blooms of Cybister Amaryllis (varieties of the South American species Hippeastrum cybister) look like exotic tropical birds but the bulbs are as floriferous and easy to grow as their bigger cousins. The dramatic Cybister Amaryllis naturally make smaller bulbs and flowers.

The vibrant coral flowers of ‘Sunshine Nymph’ are detailed with pink undertones and white stripes.

Nymphs are a distinctive, carefully-bred class of Amaryllis with exceptionally large and heavily petaled flowers on very strong stems. As the photos confirm, blooms are nearly as wide as the pots they grow in and each stem is guaranteed to produce four flowers, a rarity among doubles.

These red-and-white, lightly ruffled blooms of ‘Spotlight’ take center stage and light up even the darkest winter days with white lower petals that are etched with dark orange flecks and soft brushstrokes.

Amaryllis flowers come in a variety of colors, or even shades of colors. These types are known as bicolor Amaryllis. Bicolor means the Amaryllis flower has two colors on the same bloom.

As iconic as its Hollywood namesake, ‘Marilyn,’ this perfectly proportioned beauty turns heads with voluptuous double white flowers and faint green undertones.

Double Amaryllis are popular for good reason. Their shapely blooms and rich colors light up a cold day like nothing else we know.

These enormous, open-faced, solid pink blossoms of ‘Lagoon’ cast a spell of tranquil beauty.

Amaryllis flowers come in a variety of shapes and sizes, including single-flowered varieties. This means they have a single layer of petals that form the flower.

To learn more about Amaryllis, watch our short video below, ‘How to Pot and Care for Amarylls.’

 

It’s Cleanup Time!

Garden Maintenance
The garden staff is busy cleaning and carting away spent annuals, and the foliage and faded blossoms of some perennials and shrubs.
Faded annuals, and the foliage and spent blossoms of some perennials and shrubs have been pulled out and are ready to be carted away.

Here in northwestern Connecticut, the fall foliage show is nearing its peak, and in some places, the leaves have begun to fall. They rustle at our feet as we go about our rounds. This is Nature’s way of telling us it’s time to clean the garden.

Clearing out beds and borders means different things to different people. Some gardeners clear every last leaf and past-bloom plant from their gardens while others find reasons to leave everything as is until spring. We fall somewhere in the middle. We believe that maintaining a healthy garden and nutritious, well-structured soil requires different cleanup rituals for different garden spaces. At the farm, here’s how we go about it:

The spent flowers of a Zinnia are beginning to develop mold. Those will be cut and discarded, but for the time being, there is a certain beauty in decay.
The spent flowers of a zinnia are beginning to develop mold. They’ll be cut and discarded, but for the time being, there is a certain beauty in decay.

Remove Most Annuals

For starters, we remove most annuals. In general, these plants are easy to spot because after the first hard frost, many of them, including impatiens, begonias, and coleus, have withered and turned brown. If the spent foliage and blossoms on these plants are free of mold and disease, we put them in the compost pile. If we see traces of powdery mildew (zinnias are often afflicted), downy mildew or other diseases, the plants are put into trash that’s hauled off the property. Keep in mind that any mold or disease that’s allowed to stay in the garden will overwinter and reinfect new growth in spring.

Some annuals argue to be removed a bit later in the fall. “If the Cosmos or verbena bonariensis are still green and self-sowing, I will leave them until later,” says nursery manager Barb Pierson. “Plants like Rudbeckia ‘Prairie Sun,’ which can overwinter here, will be left until spring. Kale is pretty late in the season, too.”

Cleaning out the beds beside the store. Rudbeckia 'Prairie Sun' bows out after an exceptional summer performance.
Cleaning out the beds beside the store, Rudbeckia ‘Prairie Sun’ bows out after an exceptional summer performance. (Because the plant is sometimes hardy in our zone, some gardeners keep it in to see if it returns in spring.)

Clean Out the Vegetable Garden

In the kitchen garden, Pierson removes all vegetable plants, paying special attention to any varieties, such as tomatoes, that may have fungal leaf spots and mildew. Afflicted plants must be completely removed and put into the garbage (or carted to the dump) or the same afflictions will plague next season’s plants. “Most vegetable plants are best removed unless you are growing fall lettuce or other cold crops here in New England,” Pierson says. “If we plan to plant tulips in the raised beds for a nice spring show, this is the time to do it. If we don’t plant bulbs, we will remove any soil that comes up with the vegetables and add fresh soil in spring. Compost can be added in the fall if it is fresh, but we prefer to do it in the spring because we use fully composted material. Each spring, we replace the top 1/3 of soil – at the least – for best results. Mulching can attract digging rodents so we don’t mulch the beds during the winter months.”

Perennials & Shrubs

In the perennial garden, our methods vary. In the shady beds near the store, our gardeners clean and clear away dead and dying foliage. They cut back ferns, hostas, astilbes, and ligularias. Why? One year, when they let the decaying leaves lie, they discovered that the cushy, warm environment attracted critters who dug around and sometimes nested in the leaf mulch. That would have been all right except the critters didn’t stop at the mulch. They burrowed into the roots of the plants, inadvertently killing a few, and those had to be replaced the following spring.

Browning fern foliage being yanked out and hauled away.
Browning fern foliage is yanked out and hauled away.

In areas where critters don’t pose much of a problem, Pierson and many others believe that the decaying leaves of most deciduous trees are beneficial to the garden. For starters, they form a natural leaf mulch that provides insulation for perennials and shrubs. Oak leaves, which are waxy and don’t easily break down, are particularly good for insulation. Mounding them around perennials and shrubs protects the plants from seasonal temperature swings. Pine needles are another fine insulator, and they’re especially good for acid-loving plants including rhododendrons and azaleas. Leaves that break down more readily such as maple, ash and birch leaves add organic nutrients to the soil, and help improve soil structure.

The foliage of Phlox 'Robert Poore' is covered in powdery mildew. The plants need to be cut at the base and removed or the mold will return in spring to re-infect the plants. It won't inhibit the blossoms, but it's not much to look at.
The foliage of Phlox ‘Robert Poore’ is covered in powdery mildew. The plants need to be cut at the base and removed or the mold will return in spring to re-infect the plants. It won’t inhibit the blossoms, but it’s not much to look at.

As with annuals and vegetable plants, it’s important to note that any perennials or shrubs that exhibit mold or disease should be cut back, and the spent foliage and blossoms should be carted away to the trash (not the compost pile). Plants like Perovskia (Russian Sage) should not be cut to the ground, Pierson says. “The most important thing to remove is the foliage – not the crown or stems – so I would say remove leaf litter and prune stems as you would for that variety, in general 3-4” above soil level.” Some of the perennials and shrubs most commonly affected by powdery mildew include peonies, monarda (bee balm), phlox, and roses. As with vegetable plants and annuals, if you leave afflicted plants in the garden, the mold and disease will overwinter and reassert itself in spring. The mold won’t interfere with blossom production, but it will detract from the beauty of the foliage.

We like to leave the seed heads of Echinacea in the garden. Birds feed at them, and they also look lovely dusted in snow.
We like to leave the seed heads of Echinaceas (Coneflowers) in the garden. Birds feed at them, and they also add winter interest when dusted in snow.

As you cut down bee balms, phlox and peonies, keep in mind that there are other perennials and shrubs you’ll want to keep. While ornamental grasses can be cut back in fall (leaving 6” of growth to protect the crowns), the argument for leaving them until spring is that they look quite lovely dusted in snow. The seed heads of Echinacea and the berries of Ilex verticillata (winterberry) feed the birds as winter sets in. The pods of Asclepias, the flower clusters of Sedum ‘Autumn Joy’ and Eupatorium, and the seed heads of Echinaceas (Coneflowers) all provide winter interest.

Purple kale won't be taken out of the garden until a deep freeze. For now, the intense color adds beauty to the autumn landscape.
Purple kale won’t be taken out of the garden until a deep freeze. For now, the intense color adds beauty to the autumn landscape.

So clean as much or as little as you choose depending on the types of plants you have in your garden. But whatever you decide, it’s time to grab your rake and pruners, and spend a few days in the glorious autumn weather putting your garden to bed.

In one of the display gardens, the bright lavender blossoms of the autumn-blooming Colchicum have popped up amid a sea of lime-colored Sedum 'Angelina.' We won't be cutting these!
In one of the display gardens, the bright lavender blossoms of the autumn-blooming Colchicum have popped up amid a sea of lime-colored Sedum ‘Angelina.’ We won’t be cutting these!

Climbers in the Garden

Clematis, Climbing Roses, Garden Design, Vines

Elevate your garden design by incorporating climbing vines and plants into beds and borders, or by using them to soften fences, walls and wellheads. Smaller climbers, including some Clematis varieties, can be used to add vertical interest to container pots or to skirt the trunks of deciduous trees. We offer all of these plants for fall-planting because autumn’s mild weather gives them a chance to settle in under stress-free conditions. They develop root systems before going dormant for winter. When spring comes, they’re poised to begin growing above ground, and they have a nice head start on vines and climbers planted in spring.

Clematis Rosemoor™ Gardini™

When you hang the name of a Royal Horticultural Society garden on a new introduction, it had better be good. Clematis Rosemoor™ Gardini™ is better than good. It comes from Raymond Evison’s superb breeding program on the Isle of Guernsey. Its showy 5″ purplish-red blooms appear on old and new wood, which means flowering is almost nonstop from early summer to fall.

Dawn & Dusk Rose & Clematis Collection

Stunning aerial liaisons can be arranged by pairing two different vines or climbers. We especially like deep purple Clematis ‘Etoile Violette’ with the blush pink, double-flowered Climbing Rose ‘New Dawn.’ The Clematis clambers up the Rose’s thorny canes and obligingly places its flowers next to those of its host. When the two are at their peak in early July, the display is pure magic, and both generally offer some repeat bloom through summer. ‘New Dawn’ is sweetly fragrant and disease-resistant, especially to black spot, the bane of many Roses.

Clematis Petit Faucon™ Gardini™

Unusual blossoms made up of 4 slender, twisting petals in vivid purple blue with contrasting yellow anthers appear over a long season on this compact, non-clinging vine. At a mature height of 3-4’, it’s ideal for containers, or for climbing over shrubs. Winner of the RHS Award of Garden Merit.

Climbing Hydrangea

Hydrangea is a valuable genus of some 100 species of shrubs and vines grown for their large and very showy flower heads. Hydrangea anomala petiolaris, or Climbing Hydrangea as it’s more commonly called, is a vigorous deciduous vine from Japan and Korea whose heart-shaped foliage and large white clusters of June flowers make it an attractive covering for a wall, fence, or large tree.

Rose ‘William Baffin’

Climbing Rose ‘William Baffin’ has yet to receive the attention it deserves. It bears semidouble, deep pink flowers in abundance in late June, with recurrent bloom well into fall. It is also exceptionally vigorous and hardy, the only recurrent climber available to gardeners in Zones 3 and 4. It’s destined to become one of the most enduring Roses of our era.

Wisteria Lavender Falls

Wisteria is a genus of deciduous vines whose lovely, fragrant flowers and almost overwhelming vigor make them useful in a wide variety of settings. Wisteria Lavender Falls, originally grown in Oklahoma, is an outstanding variety that has blue-violet, 9–20″ cascading racemes that have the scent of grape jelly. The really exciting part is that they reappear several times during the summer.