DIG DEEPER

The Difference Between Bulbs, Corms, Tubers, Roots

Today, people commonly use the term "bulb" to refer to any plant that stores its own food underground. But, in truth, many popular "bulbs" are not true bulbs at all. These include corms, tubers and roots and, while they all produce beautiful flowers, technically the plants are different.

Bulbs and corms look quite similar. Bulbs store their food in their scales while corms store food in their basal plate. For that reason, corms have smaller scales and an enlarged basal plate. This gives corms a flatter shape versus the rounder shape of bulbs. Examples of corms are crocuses and gladioli.

Tubers and roots come in a variety of shapes including cylindrical and flat. Many come in clusters and have no protective tunic.

Tubers and roots are really just enlarged stem tissue. Familiar tubers include dahlias and begonias.

Hardiness

As a rule, spring-flowering bulbs are "hardy." This means that they can survive the cold winter months after being planted in the fall. Indeed, hardy bulbs require a period of cold to activate the biochemical process needed for flowering. Many hardy bulbs can be left in the ground to flower year after year.

Most summer-flowering bulbs are "tender." Tender bulbs cannot survive harsh winter conditions and are planted in spring after the final frost. In fall, these bulbs must be dug up and stored indoors. One notable exception is the lily.

About Winter Mulch

Most people think winter mulch is like a thick sweater that spring-flowering bulbs should put on before the cold sets in to keep them from freezing. But it's really more like a scarf that should be applied once the ground is already cold. This keeps the soil temperature consistently cool over the winter, helps retain moisture and minimizes damage from frost. Mulch too early and the overly warm soil conditions can promote disease and give mice and other unwanted pests a cozy place to build their winter den.

Naturalizing simply means that a bulb flowers again after the first year. Some bulbs are planted as annuals and will bloom only one season. All the food they need to flower is contained in the bulb. Naturalized and perennialized bulbs, however, need your help to get the food to recharge and regenerate for the next season's bloom.

Fall of the first season: When planting, work a good organic compost or well-rotted cow manure into the soil. Apply a layer as a top-dress or mulch, as well. Or, add compost or peat to the soil (for drainage) and top-dress with fertilizer: 9-9-6 NPK slow release or either 8-8-8 or 10-10-10 NPK fast-release soluble fertilizer (about one tablespoon per square foot). The slow-release method is, frankly, the easiest approach.

Come spring: If you used slow-release fertilizer, don't do anything. If you used fast-release fertilizer, apply a nitrogen-rich, fast-release NPK fertilizer just as the shoots first emerge from the soil. Fertilizing at bloom time or after can lead to disease issues.

Fall of the second season: Fertilize again by your method of choice.

Dieback: For all bulb plants, let the green foliage die back naturally after bloom for approximately six weeks. This is the time when photosynthesis creates and stores the sugars that fuel next year's bloom. Resist the urge to tidy up fading foliage or mow over it. An easy disguise is to interplant hostas, coral bells, lilies or other perennials that leaf-out early in the spring.

Deadheading: Tulips, yes. Daffodils and others that naturalize, no. Fading tulips will form seeds that sap energy from the bulb, so snip off the fading flowers.

Sometimes, naturalizing just doesn't happen. It could be the setting, the soil or the sun. Heavy summer watering can be a factor, too. And sometimes, it could just be the type of bulb. Some fritillarias and hyacinths, for example, just have a hard time making a strong comeback.

While planning your long-term naturalized bulb garden, think about adding a few stunning short-term, non-naturalizing bulbs in high visibility spots. You'll bring whimsy to your garden and be able to experiment with different bulbs year after year.

A perfectly placed pot or container with even just a few flowers can instantly perk up any spot, which might explain why they're a favorite of city terraces and balconies. There are hundreds of attractive ways to use containers and you only have to keep in mind that your plant choices will need to tolerate wind. Lower-growing crocus, scilla, chionodoxa and grape hyacinths are great choices, along with shorter tulips and rock garden daffodils.

When planting your container in the fall, there are a variety of ways to plant them depending on your intended effect:

• For massive color effect, plant with a single variety of bulbs
• For continuous spring color, plant several kinds of bulbs that have successive flowering periods. Use the "lasagna technique" of planting bulbs in multiple layers, with early-flowering bulbs in the upper layer and bulbs that flower later and last in the middle and deepest layers.
• For a "mini-garden" effect, choose multiple containers and pots of various sizes and fill them with the colors and bulbs of your choice

Terracotta pots, plastic planters, molded fiberglass planters, wooden half-barrels, wicker baskets, ceramic pots, old wooden wagons, wheelbarrows, and even tires — all make for useful decorative containers. If you have more than one pot, group them together for greater visual effect and to make watering more convenient.

To plant in containers, follow these simple steps:

Step 1: Buy soil

Commercial potting mixes like those sold at most hardware stores and home and garden centers are the best soil for container plantings. Generally, they're richer, cleaner, more insect- and disease-free and lighter in consistency than most garden soil. Most important, potting soil retains water for a long time, which keeps flowering bulbs from drying out during growth and flowering. Replace the soil every growing season or, if you plant bulbs as tub plants, be sure to enrich the soil with a fertilizer tablet in early spring, which will gradually release nutrients to the roots for at least four weeks.

Step 2: Allow for drainage

Be sure to keep the drainage holes clear since plants cannot survive in waterlogged soil.

Step 3: Choose a deep enough container

Check the suggested planting depth on the plant label and be sure your container is deep enough for your selections.

Step 4: Add Soil

Fill the pot 1/4 to 1/3 deep with soil, position plants at the proper depth, then fill in additional soil up to 1" (2.5 cm) below the rim of the pot to allow for watering. Use this top inch for mulch, if needed.

Step 5: Double Potting

You can display the planted container as is or you can "double pot" the container by sinking it into a more decorative one. Be sure water can't collect in the base and drown the inner pot. Either drain as needed or place a brick or inverted saucer in the base to elevate the inner pot.

Plant in Layers: Pots of Perpetual Spring Color

Nothing tells dreary winter that its days are numbered like a cheerful pot of tulips blooming by the front door. But did you know that by layering your container's plantings in fall you can create seemingly perpetual color in spring?

Layering, or planting "lasagna-style," is a technique that lets you enjoy successive waves of bloom in a single container by overlapping the bloom times of early, mid and late-blooming spring bulbs. Any early-mid-late combo will work and one excellent combination is to use crocus, daffodils, grape hyacinths and tulips as the early, mid and late blooming bulbs. In this particular scheme, it's the cobalt blue grape hyacinths with their extremely long bloom season that holds everything together.

Place layered pots where you'll most enjoy them: by doorways, walkways, the mailbox and lampposts, next to the garage or driveway, or even right outside your kitchen window!

The following instructions will help you get started:

Minimize Cold, Wind Exposure

The larger the pot, the greater the protection it provides. To protect bulbs in colder climates where freezing is an issue, choose a whisky barrel-sized pot or larger or place pots in protected areas, such as against a house foundation or inside a garage, until sprouts emerge in early spring. Another technique is to group large pots close together in an area away from wind and extreme cold then wrap the whole group with burlap or other insulating material. If it's simply too cold in your area to protect containers from freezing, don't try over-wintering bulbs in outdoor containers.

Positioning the Bulbs

To plant in layers, pretend you're making lasagna. You'll plant the largest bulbs 8-inches (20 cm) deep and smaller bulbs 5-inches (13 cm) deep with layers of soil under, over and in-between the bulbs. Start by filling the base of the container with potting soil. Measuring from the top rim, allow 2-3 inches (5-7 cm) for mulch and watering then measure an additional 8 inches (20 cm) to position the first layer of bulbs.

At 11 inches (28 cm) below the pot rim, place the tulips and daffodils pointy ends up. Intermix the bulbs so tulips and daffodils are evenly distributed and position them close together, even touching, to maximize bloom from this spot. You don't want bulbs touching the sides of the container since this area is most vulnerable to freezing.

Add 3 inches (8 cm) of soil around and above the first layer.

For your second layer, intermix the smaller bulbs (crocus, muscari) so they're evenly distributed and pack closely together. Don't worry that the growing sprouts will bump into one another because it doesn't happen! Like people rushing along city sidewalks, bulbs tend to grow around one another, swerving slightly out of the way.

Top off with 5 inches (13 cm) of potting soil and water well. Top dress with mulch or even pansies for an appealing touch of winter color.

Three Waves of Spring Color

As spring arrives, sit back and enjoy the show as three waves of colorful bulb flowers come up, bloom and move on:

• 1st wave of bloom, early spring: Crocuses bloom, then fade away.
• 2nd wave of bloom, mid-season: Daffodils and grape hyacinths bloom, then daffodils fade away.
• 3rd wave of bloom, late season: The same grape hyacinths continue to bloom, now joined by tulips. Then, both fade away, completing the display.

The leaves of each wave will remain to bring fullness to the display, although you may wish to snip off the faded daffodil flowers. Don't be tempted to leave the bulbs in the pot if summer flowering bulbs will be planted there next. Routine watering and fertilizing over summer will damage the spring bulbs. Once the tulip flowers fade, it's time to dig up the whole lot and replant everything in a less-conspicuous spot in the yard or garden. Choose a well-drained, sunny spot, such as along a path or side yard at the edge of the property, where the bulbs can slowly die-back. By giving them some fertilizer in fall and again in early spring there's a good chance they'll come back in future years to bloom again and even multiply.

Colors

Planting bulbs is fun, but it's dreaming up fabulous color schemes that will really get your creative juices flowing. The color palette is endless and so are the combinations that cater to the colors you love. Have a passion for purple and orange? Try rich purple tulips (Tulipa 'Purple Prince') intermixed with purple-flamed orange tulips (Tulipa 'Princess Irene'). Go bonkers for blue and yellow? Then fragrant deep blue hyacinths (Hyacinthus 'Blue Jacket') with jaunty yellow daffodils (Narcissus 'Dutch Master') may be just what you're looking for.

Keep bloom times in mind. Spring actually has three bloom seasons: early-, mid- and late-season. By choosing bulbs that bloom at different times, you'll have month after month of spring color. Plant low-growing bulbs, such as grape hyacinths, in front of taller bulbs, such as daffodils. Or mingle them all together for a more naturalistic effect.

Knowing bloom times will help you create bloom teams: flowers that come into bloom and decline at approximately the same times. While you can't expect flowers to perform in precise synchronicity, it's helpful to think of the color in your garden "building towards a color crescendo."

Then again, you could let the experts do the color work for you and just follow their lead! The following is a selection of colorful bulb combos that should bloom in a delightful display. Remember to plant in fall and forgive Mother Nature if she throws you the occasional curve.

Early-Spring — Blue, Yellow & White

Scilla siberica, Narcissus 'Tête a Tête', Narcissus 'Ice Follies'
In this spritely combo, the cobalt-blue scilla are first to bloom. They continue to bloom for weeks as yellow Narcissus 'Tete-a-Tete' joins in, followed by white N. 'Ice Follies'.

• Scilla siberica — This delicate-looking but sturdy little color machine produces stems supporting up to five bowl-shaped, brilliant blue flowers each. The flowers emerge on still-short stems, then gradually rise to eight inches (20 cm) in height by maturity.
• Narcissus 'Tête a Tête' — A miniature daffodil just six inches (15 cm) tall, 'Tête a Tête' bears an abundance of short-stemmed dangling flowers with golden-yellow outer petals that curl back to highlight deeper-yellow trumpets.
• Narcissus 'Ice Follies' — This medium height, large-cupped daffodil is a champion naturalizer, famous for its ability to "come back" each spring, often for decades in settings where it is happy. Its performance is marked by two personas: the large, frilled flower cups are lemon-yellow when they open, then fade to nearly white as the flowers mature.

Mid-Spring — Red, Yellow & White

Tulipa turkestanica, Tulipa praestans 'Unicum', Tulipa tarda
These three botanical tulips combine to charming effect in the early spring garden. If you like how they look, you're in luck, as all three are excellent naturalizers and will come back for years to come in many garden settings. Their mix of bright green, grey-green and variegated leaves with creamy white margins provide a sophisticated backdrop for their colorful red and yellow flowers guaranteed to brighten the mid-spring landscape. T. turkestanica will bloom first, joined by T. praestans 'Unicum' and slightly later, T. tarda.

• Tulipa turkestanica (Species Tulip) — This is a wild-looking species of botanical tulip with grey-green leaves and up to 12 star-shaped, malodorous white flowers borne on 12-inch (30 cm), hairy stems. Indeed these are quite attractive little flowers despite the smelly hirsute description. While appearing white at first glance, the flowers are actually flushed greenish-grey or greenish-pink on the outside, with centers shaded yellow or orange around brown or purple stamens and purple-tipped yellow anthers.
• Tulipa praestans 'Unicum' (Miscellaneous Tulip) — A bunch tulip (multi-flowering) just eight-inches (20 cm) tall, 'Unicum' has variegated leaves edged in creamy white and clusters of up to five cayenne-red flowers, each centered with a light-yellow base and blue anthers.
• Tulipa tarda (Species Tulip) — This six-inch (15 cm) tall bloomer boasts star-shaped yellow and white flowers that open wide in the sun, then close tightly overnight. Each flower is white with a greenish tinge and a vivid yellow interior edged in white. Its shiny, bright green leaves are lance-shaped, recurved and often finely fringed.

Late Mid-Spring — Red & White

Tulipa 'Mount Tacoma', Tulipa 'Red Riding Hood'
In the garden or a container planter, taller T. 'Mount Tacoma' will bloom above shorter T. 'Red Riding Hood'. This combination of white-over-red provides a fresh twist on a traditional spring garden color scheme.

• Tulipa 'Mount Tacoma' (Double Late Tulip) — With lovely, pure-white peony-shaped flowers atop 16-inch (40 cm) stems, this tulip has a commanding presence in the mid-season garden.
• Tulipa 'Red Riding Hood' (Greigii Tulip) — A stout shorty only eight inches (20 cm) high, this tulip bears plump, carmine-red flowers with vivid scarlet inner petals framing a dramatic black inner base. Its wide, soft green leaves are mottled with appealing purplish spots.

Early Late-Spring — Orange Flush

Tulipa 'Orange Princess', Tulipa 'Ballerina'
These two orange superstars, with their very different personas, make quite the duo in the late season garden. 'Ballerina' is tall, willowy and elegant with long stems and slim, elongated, marigold-orange blossoms. At half the height, peony-flowered 'Orange Princess' fills in below with a plump, colorful presence.

• Tulipa 'Orange Princess' (Double Late Tulip) — A 12-inch (30 cm) sport of lovely 'Princess Irene', this peony-flowered tulip is light-nasturtium-orange flushed with reddish-purple and glazed lightly in warm pink. Its chubby, bowl-shaped flowers are tipped with green on the outer petals.
• Tulipa 'Ballerina' (Lily Flowered Tulip) — This lovely 24-inch (60 cm), fragrant tulip technically features lemon-yellow flowers with blood-red flames, orange-yellow veins at the margins, star-shaped yellow bases, and cayenne-red inner petals feathered marigold-orange surrounding pale golden yellow anthers. But, forget all that: the overall effect is not really so complex: what your eyes see is an absolutely glorious shade of orange!

Late-Spring — Pink & Purple

Tulipa 'New Design', Tulipa 'Angélique', Tulipa 'Blue Parrot'
Tulip 'New Design' comes into bloom first, followed by 'Angelique.' Both are noted for their long bloom times in the garden. As they reach full bloom, the slightly-later blooming 'Blue Parrot' tulips join in. The purple flowers reach their peak on the far side of the pink tulips' extended bloom time.

• Tulipa 'New Design' (Triumph Tulip) — Now here is an elegant tulip that blooms on the late side of mid-season and, thus, happily teams up with earlier-blooming members of the 'Parrot' and 'Double Late' tulip groups. Its flowers are soft yellow flushed with pinkish-white and edged in pale fuchsia-red. Inside each flower cup is a surprise; here, the color is soft yellow flamed with apricot, and the base is an unexpectedly rich buttercup-yellow shown off by dark brown anthers. Even the variegated leaves are exotic — soft green edged in pale-pinkish white.
• Tulipa 'Angélique' (Double Late Tulip) — This 12-inch (30 cm) tall tulip is North America's favorite — and no wonder! Its flowers are peony-shaped, fragrant and extremely long-lived in both the garden and the vase. Most call the flower "pink." But look twice — each petal is a whorl of shades ranging from blush to pale pink to rich rose, with flushes here and there of pale green, cream and pale yellow.
• Tulipa 'Blue Parrot' (Parrot Tulip) — With its over-sized, flamboyant flower head atop a tall slender stem, this 'Parrot' tulip bobs and flutters like its tropical namesake. Its bright, violet-blue flowers, flushed bronze-purple inside, are wavy-edged and fringed like feathers.
  • Tulipa 'Apricot Parrot' (Parrot Tulip) — This fragrant late bloomer presents a more flamboyant persona in the garden with ruffled, feathered petals reminiscent of tropical bird plumage. Each apricot flower is flushed and flamed with color ranging from creamy white to yellow, salmon-pink and soft green. It stands 16- to 18-inches (40-45 cm) tall.
  • Tulipa 'Upstar' (Double Late Tulip) — 'Upstar' seems to be pink perfection in a late blooming tulip, but in fact it is a creamy white tulip that "fades to pink." This unusual effect occurs as the petals mature and broad bands of purplish-rose emerge to alter the flower's coloration. The peony-shaped flowers are borne on sturdy 18-inch (45 cm) stems.
  • Tulipa 'Spring Green' (Viridiflora Tulip) — A translucent beauty of shimmering white flushed with pale green, this lovely green-feathered, ivory-white tulip strengthens the presence of its more stark dark-and-bright bloom partners. It is 20-inches (50 cm) tall, thus blooms right beneath the heads of 'Queen of Night'.
  • Tulipa 'Queen of Night' (Single Late Tulip) — Introduced in 1944, 'Queen of Night' is still considered the blackest tulip ever bred. This classic cup-shaped tulip, 24-inches (60 cm) tall, is a velvety dark maroon or mahogany, depending on the light. In the shade, the flower can appear to be pitch black.

Late-Spring — Peaches & Cream

T. 'Apricot Parrot', Tulipa 'Upstar', T. 'Queen of Night', 'T. Spring Green'
How romantic can tulips be? To see, just plant this awesome team! A tip: pair any two, three or all four of these beauties for an array guaranteed to take your breath away. Each has an exquisitely lush flower noted for unusual coloration. Each is a top-performer in the garden or the vase. Expect 'Apricot Parrot' to begin blooming first, quickly followed by the other three.

 

As most bulb gardeners eventually learn: it's their world, we just plant in it. And the extent to which squirrel, deer, rabbits, voles, moles and other nuisances devour your garden has a lot to do with your level of preparedness. Pest problems can happen in any season although fall and spring are peak periods for plunder.

Fall is a great time to marshal your defenses, starting with a good garden clean up. After planting, remove debris left behind by your bulbs and the bags they came in. You can literally throw critters off the scent by removing anything that whiffs of a delicious bulb feast. Also, consider applying mulch after the ground has cooled, not before. Mulch helps retain soil moisture and keeps soil temperature consistently cool. Applied too early in fall, it will keep the earth warm and invite small creatures to camp out for the winter.

Know Thy Enemy

Who or what, exactly, is nibbling the nasturtiums and devouring the daisies? If you live in North America, the culprits are probably deer. After a long winter with little to eat, they're particularly ravenous for anything green, young and edible. Rabbits, while pickier eaters, are also happy to taste-test anything tender. In the fall, squirrels and chipmunks are particularly pesky at planting time and only too happy to devour tulip, lily or crocus bulbs (but not daffodils which have a terrible taste). Bulb-scented debris will lead them straight to buried treasure, so be sure to clean up your bulb bags and the papery skins after planting.

Underground, there are even more culprits: moles, voles and mice love the roots of trees, shrubs, succulent plants and flower bulbs. Not to mention the groundhog (aka woodchuck), a tunnel master who finds any number of garden plants appealing whether they are above the ground or below.

What to Do About Pesky Pests

If only there were a single magic solution to solve the animal pest problem once and for all. Since that's impossible, the best strategy may be to find the deterrent that works best for your situation. Pest control options are grouped into five major categories:

• Barriers
• Sensory deterrents
• Vegetative deterrents
• Animal deterrents
• If you can't beat 'em, join 'em.

About Barriers

Barriers are the most straightforward and, many say, the most effective deterrents. The strategy is simple: what they can't touch, they can't eat. Barriers include fences, chicken wire and screening.

For deer, a fence at least seven and a half feet high with an additional overhang of chicken wire will serve well. Even better: two fences (one high, one moderately high) spaced about three feet apart. Deer can either jump something very high or something very wide, but can't do both at once. Don't worry, they'll be too afraid of getting caught between the two to even attempt it. You may decide that plastic fencing and netting from a garden center or other retailer is more appropriate for your area, or if you live far from neighbors and don't have small children, you can even consider installing an electric anti-deer fence.

For groundhogs, fences don't need to be high, just deep. About three feet deep should do the trick.

Chicken wire can be an effective barrier. Use it to form a cage over young plants or as an underground cage in which to protect bulbs from burrowers. Some people take a casual (but very effective) approach to protecting bulbs from squirrels: they just throw on an old window screen after planting and take it up once the ground has settled or frozen.

Sensory Deterrents

Sensory deterrents work either by offending the pest's sense of smell or taste, or by exciting his sense of fear and caution.

Cayenne pepper sprinkled protectively on the ground is one method some people attest to. Others point out that this method is exceedingly cruel. Squirrels, for example, can easily get the pepper in their eyes. While trying to rid themselves of the noxious stuff, they can unwittingly scratch out their own eyes.

Since the goal is to rid ourselves of pests, not force them to suffer inhumanely, other sensory deterrents suitable for squirrels, rodents and deer include:

• Human hair clippings, scattered around (though in urban settings this may be associated by squirrels with handouts by humans).
• Predator smells, such as lion's dung or urine from the zoo, commercially available predator scents or even human urine.
• Egg mixtures, either commercially available or of the homemade variety, which smell like, well, rotten eggs.
• Irish Spring soap hung in mesh bags around the garden perimeter. Some people swear it works!

All have their champions and detractors. What works in one garden doesn't work in another. The key is to experiment and find out what works for you. They're at least worth a try.

Vegetative Deterrents

The idea behind vegetative deterrents is to surround the plants pests are attracted to with ones they aren't. Deer, for example, don't like thorny things. They also don't eat anemones, astilbes, junipers, foxgloves, daffodils, ferns, and grasses, to name a few. So you could effectively cordon off your garden by planting some of these suggestions or, if your own nose can stand it, fritillaria imperialis. Its skunky scent repels deer and many other creatures. Squirrels and other small creatures won't eat daffodils and other narcissi bulbs, so make good all-around choices.

Animal Deterrents

You can also plant canis lupis familiaris in your yard. That's Latin for "big dog." And by that we mean just a big, frisky fellow with a loud bark, not an attack dog. You'll find plenty of eager candidates at your local animal shelter, who in return for your love and care will happily bark their heads off in defense of your plantings. If you go this route, do the right thing and keep Fido fenced in a back yard, or leashed on a line run. Domestic dogs that roam free have been known to revert to their primal instincts and to attack and kill lame deer and fawns.

If You Can't Beat 'Em, Join 'Em

In a little reverse psychology, it's been suggested that one way to keep animals from feeding on your plantings is to feed the animals. The idea being to make it so easy for them to eat that ravaging your garden seems like too much effort. It's up to you whether you subscribe to this approach — some swear by it, others believe it only encourages more pests — but one thing's for sure: in the end, the most appropriate pest control measure is whatever works best for you.

Animal-Resistent Bulb Species (by blooming time)

Click here to see a full listing of animal-resistent bulb species.