Beautiful Bulbs -September/October 2009
Tulips, daffodils, hyacinths and more
by: Hilary Newell
Having deer come into our yards and eat our tulips is probably our biggest problem with these lovely flowers on Nantucket, although by 1637, tulip mania became enough of a problem to the Dutch that it caused a major economic crisis in the Netherlands.
Around the same time, Europeans were beginning to cultivate daffodils as a garden plant. Previously found only in the wild, the garden daffodil’s ancestors, some 26 to 50 species depending on what source you use, are native to western and southern Europe and the areas around the Mediterranean Sea and the Middle East, and have spread over the whole world ever since. Around 1900, there was an explosion in popularity of daffodil bulbs, and since then, hybridization has grown the worldwide collection to over 25,000 varieties.
Hyacinths are native to Turkey, and were a small part of the bulb trade of the 17th and 18th centuries with over 2,000 cultivars available. Indigenous crocuses have been found for hundreds of years in a wide swath from Afghanistan to Spain, though the hybrid crocus that we know today has only been popular since the 1940s.
Spring-flowering bulbs certainly have an interesting history, but it is their use in today’s gardens that provides all the color. But why is the topic in a fall issue of a magazine? Spring bulbs bloom in … well … spring, but the only way they can do that is if they are planted in the fall. Technically, not all of the plants referred to here are bulbs. Some are corms, tubers or rhizomes, but for brevity’s sake, they will be called bulbs.
Certain types of bulbs are good for naturalizing, that is, planting in drifts of hundreds to thousands of bulbs, creating the effect of a carpet of color. Over the course of a few years, the bulbs multiply and the drift gets thicker and wider, providing much needed-color before trees leaf out and before other flowers begin to bloom. Here on Nantucket, one can see drifts of daffodils along Milestone Road and alongside yards and fences all over the island. All this is made possible by the fact that the genus Narcissus is poisonous and the deer and rabbits won’t eat them. Occasionally a peek into a yard will give you an eyeful of color early in spring, when the crocuses are in full bloom.
Bunnies in my yard will occasionally leave them alone long enough for us to enjoy them, but most of the time they get eaten. For those people lucky enough to not have a rabbit problem, crocuses are a great addition to the yard. They grow right in the grass, and will bloom and ripen before the lawn needs to be mowed the first time. By the time the lawn gets mowed, the crocus foliage will have matured and disappeared back underground.
It is a bit trickier to find a good place to naturalize daffodils in your yard. With all spring bulbs, the foliage needs to ripen and turn yellow before it gets cut back, as the leaves are used by the plant to photosynthesize and make food to replenish the bulb for the following year. Without the foliage, photosynthesis won’t occur, and the bulb might not generate enough food to produce a flower the following year. Planting daffodils near a fence or at the edge of the yard may work well for naturalizing, as you can let the grass grow right along with the foliage and mow it all down at the same time. That is what happens along our roads here. The roadside grass is not mowed down until it gets quite tall, and the daffodil foliage gets a chance to ripen and the bulb matures. The bulb will rest underground for the remainder of the year. In your garden, it is advisable to leave the daffodil foliage until around July 4.
Depending on your level of tidiness, ripening foliage can be handled in a couple ways. Most of us ignore it until it looks so untidy that one day in late June or early July we cut it back. Some gardeners prefer to tie the foliage together like a wheat shock, or bent over and tied to make it look neater. The important thing is to be sure it continues to get sun and water. The best time to feed a bulb is when the foliage is starting to grow, before the flower is open.
Windflower (Anemone blanda) is also great for naturalizing. It will form a nice clump in your flower border and is a reliable perennial bulb. They are completely maintenance-free, once they are established. These three- to four-inch beauties are a welcome sign of spring.
Alliums, grape hyacinths (Muscari,) squill (Scilla, also known as bluebells), snowdrops (Galanthus) and lily of the valley (Convallaria majalis) all naturalize well. The lily of the valley is particularly nice in the shade. These so-called minor bulbs would all work well in a yard. Others include star of Bethlehem (Chionodoxa) and winter aconite (Eranthus). Plan on purchasing quantities of bulbs to get started, and plant in clusters, planting as close as the directions suggest. The more bulbs you plant, the more effective the display.
Tulips can be problematic on Nantucket. Unfortunately, they are yummy hors d’oeuvres for deer and rabbits. If you are lucky enough not to have that problem, go ahead, plant and enjoy them. There are few things as pretty as a bed of tulips in the spring. But do not expect your hybrid tulips to come back year after year looking as lovely as the first year you planted them. Our summer climate is very different from where these plants originated. Tulips are native to the mountains of central Asia, where the hot, dry summers are preceded by cool, wet springs. Hybrid tulips are bred from these plants and they really prefer the same conditions. Our summers are usually too moist for tulips to thrive year after year. Tulips can sometimes last for two to three years here, but more often than not, they will bloom the first year after planting, and then they get smaller and smaller and eventually disappear.
You may have better luck with species tulips like Tulipa saxatilis, clusiana or humilis. These often prove to be hardier and naturalize better than their hybrid offspring and are available at island garden centers and from many mail-order bulb catalogs. The Dutch growers have developed some perennial tulips that they claim will bloom for five years with consistent quality, and the University of Michigan is continuing to research long-lived bulbs. Hyacinth bulbs seem to suffer from the same short lives, though some species hyacinths will last for many years.
Tulips can provide nice temporary color. If you are in love with tulips like I am, you can plant them in pots in the fall. Using a regular potting mix, you can plant tulips so they are almost touching. The rule of thumb is to plant them to a depth of two to three times the height of the bulb. That means that a bulb that is two inches tall should be planted about six inches deep. In a pot, though, it isn’t necessary to plant quite that deep. Add some organic bulb fertilizer when you plant, water well, and hope for cold weather. Remember, good drainage is essential because bulbs do not like being wet in winter. A small pot could go in the refrigerator for the winter, but a large pot could stay outside. It is even advisable to dig a hole in which to set the pot up to the level of the soil, then dig it out in the spring (before the deer discover it) and put it in a safe spot. You can mix up bulbs in a pot, too, planting several different types. Choose varieties that bloom at different times, and your pot can be a source of color for over a month. Place daffodils down the furthest, add some soil, add a layer of alliums, cover with more soil, then plant crocuses at the top of the pot. In the spring, the crocuses will bloom first, then the alliums, then the daffodils. Be sure the pot doesn’t dry out too much as the bulbs start to emerge.
Some people have difficulty in telling which end of the bulb is supposed to go up. Most bulbs are pointy at the top and flat at the bottom, but that is not the case for all of them. If there are small hairy roots sticking out, generally that side is the bottom. If you really can’t tell, take your bulb to your garden center and ask the horticulturist for some advice.
Bulbs that are made to bloom at a time that is not normal for them are said to be “forced.” Hyacinths and certain narcissus are probably the easiest. Good timing can give you color and scent in your home for most of the winter. Hyacinths don’t even need soil to force. They will grow in water alone, and there are specially-designed vases to hold the bulb upright while it is growing. When forced like this, these bulbs are a one-shot-deal. It is next to impossible to ripen forced bulbs to produce as well as they did the first time.
Planting in the ground is a different story. Spring-flowering bulbs require a sustained dormant period in which they remain chilled at a steady temperature for a certain amount of time. The time and temperature requirements vary with the type of bulb. Paperwhite narcissus (Narcissus tazetta) is not, in fact, a spring bulb. These fragrant beauties are not hardy in our Zone 7, yet they do make easy-to-grow gifts, for a friend or for you. Available in catalogs and garden centers, they provide a relatively inexpensive way to grow something scented in the house most of the winter. They do not require a cold treatment, as their flowers are already formed and waiting for the right conditions to pop out of their skin. They require only to be planted in a shallow bowl of stones and water and placed in a bright spot. Too little light will cause the foliage and stems to grow long and weak, but interestingly, researchers at Cornell University have found a unique solution to this problem: alcohol (gin, vodka, whiskey, rum or rubbing alcohol). When these plants are grown with a dilute solution of alcohol, the foliage will reach about one-third to half their normal size. The flowers will grow to their normal size and remain just as long. And the fragrance will fill the room! It surprised me to find that some people don’t like the fragrance of these narcissi. Commercially there are many types available, each with its own unique fragrance. A little online research will yield the correct proportion of water to alcohol. As with people, moderation is the key!
Ranunculus is another spring bloomer and a member of the buttercup family. Not hardy outdoors in our climate, they need to be grown in pots in a temperate environment, like a greenhouse or a sunroom. The flowers of the ranunculus consist of several layers of fleshy petals in bright colors. The corms are shaped like little claws, and should be planted with the claws pointed down. Water well and place in a sunny window to wait. If you plant these indoors in January or February, you will have them ready to go in your spring window boxes by mid-April. They look great planted with violas and pansies and other cool-weather-tolerant plants like candytuft and hyacinths. Once warm weather hits, they stop blooming, so it’s best to just pull them out and replant your containers with summer flowers.
Of all the types of plants that a gardener can cultivate, bulbs arguably have the fewest problems and the best satisfaction rate. Most are not susceptible to insect or disease problems, and once they are planted, it takes very little care or maintenance to have continual bloom from March into early summer. Integrate bulbs into just about any garden or container-planting plan, and they can reward you with seasons of bloom. True harbingers of spring, bulbs signal the rebirth of the earth and hopes for a new growing season.
Hilary Newell is the greenhouse production manager at Bartlett’s Farm, and remembers the thousands of bulbs her grandmother planted for her children and grandchildren.