Tips on tulips, daffodils, and other spring flowering gems

NO planting adventure do we love more than tucking little brown-skinned bulbs into their winter beds so they can spring forth in a riot of color when days grow warm again. In the United States, 1 billion bulbs are now imported each year from the Netherlands. Just six years ago, the numbers were half that amount.

The US is now second to West Germany in bulb imports, but a way down the list in per capita purchases.

A recent survey shows that 70 percent of American gardeners know only about tulips. Forty percent know something about daffodils, and 25 percent are familiar with crocus. Only a small percentage knows anything about minor bulbs.

This time of year our mailbag is full of inquiries about bulbs. We're happy to help folks better understand the culture and charm of the spring-flowering gems.

Varieties to choose.

Too many colors, shapes, and sizes would make a planting look too cluttered. It's more pleasing to plant clusters of one or two colors of tulips and/or one variety of daffodils (or vice versa).

Also add a border of one of the minor bulbs. Some to choose from would be: Scilla siberica (sky blue); Puschkinia libanotica (pale blue); Scilla campanulata (wood hyacinths), white, pink, blue; Muscari (grape hyacinths), blue or white.

It's helpful to study bulb catalogs for colors, heights, and blooming dates to aid in deciding which go well together.

For rocky soil and rock gardens.

Any of the above-mentioned minor bulbs would work well. Others might include Fritillaria meleagris (guinea hen flower or checkered lily); Chionodoxa lucillae (glory of the snow), lilac blue; crocus (many colors); Galanthus (white snowdrops); Leucojum vernum (spring snowflakes); Anemone blanda (windflowers), many colors of small daisylike flowers on short stems.

Planting time.

Depending upon where you live, hardy spring bulbs can be planted from September on through December, or until the top of the ground freezes.

Bulbs do best if they are in the ground long enough to form a good root system before ground freezes around them. They are planted in fall because they need a cool period to trigger their blooming mechanism.

If watered when planted, bulbs start forming roots almost at once. We like them to have at least four to six weeks before ground freezes solid.

Freezing is not necessary for bloom, but generally speaking, a cool period with a temperature of 40 degrees F. or less for eight to 10 weeks promotes good blooms. Commercial growers manipulate temperature more precisely.

Planting in the South.

Gardeners in the South should make sure the bulbs have been precooled. This is done by either the wholesale distributor or the retailer. The bulbs are usually cooled in the case by putting them under refrigeration for the specified length of time before sale. Then bulbs will form roots during the cooler months.

Blooms are not usually as large as those of Northern planted bulbs. Some gardeners cool their own by storing them in paper bags in a refrigerator for 10 weeks.

Fertilizing.

Ideally, bulbs like a slightly acid soil and benefit from fertilizer with a high phosphorus and potassium content. We have used liquid plant food to water and feed them at the same time. Other times, we have mixed in dry fertilizer as we worked up the soil.

Many garden stores now have special bulb food, so amateurs can easily follow directions. Old-timers used bone meal, but today's product is inferior. If rain has been sparse, do water after planting.

Soil preparation.

Bulbs will tolerate almost any kind of soil except that which is poorly drained or like cement. If it is hard and lumpy, your soil needs to have organic matter mixed into it before setting the bulbs. Spade up the top eight to 10 inches of soil, and add an equal amount of organic matter such as rotted leaves, sphagnum peat moss, or rotted compost - or a mix of all three. Be sure it is spaded in evenly so that no chunks of clay are left intact.

Digging, spacing, and mulching.

If you have a small area and a mixture of different-size bulbs, you can space bulbs on top, then set them in with a trowel or bulb planter.

We find mulching helpful. Our winters have become more dry, with less snow cover - almost none of it the past two years. And we have had more beautiful blooms, and larger ones, since we started mulching with leaves several inches thick.

Depth.

Bulbs are graded in centimeters of circumference. Tulips may be 12 centimeters or more (top size) or 11 to 12 cm (first size). We do not feel that smaller, bargain bulbs are worth the trouble.

Narcissus may be labeled DN, plus a number. This means double nosed and a certain grade according to circumference.

For years we have been planting early tulips 4 inches deep and 5 inches apart; midseason and late tulips, 6 inches deep; large narcissus (including daffodils) 6 inches deep and 6 inches apart; hyacinths, the same; small flowering narcissus, 4 inches deep and 6 inches apart. All minor bulbs are planted 3 inches deep and 3 or 4 inches apart.

Some folks use the planting depth rule of three times the diameter of the bulb at its widest part.

Naturalizing.

Bulbs are planted in a natural setting to look as though they had just sprung up without human assistance. Ideal naturalizing areas might be a stream or pond bank, a meadow, an old orchard, or a sparsely wooded grove of deciduous trees where sun can shine through in early spring before leaves appear.

Daffodils are ideally suited, because they are free of insects and diseases. They also become permanent, perpetuating themselves almost indefinitely.

Neither tulips nor hyacinths fulfill the latter requirement, but many minor bulbs fit well with daffodils. It is better to have drifts or groups of one solid color, with space between, as opposed to a busy mix of several genera, species, and colors.

Daffodils or narcissus?

Botanically speaking, both daffodils and narcissus are narcissus, of which there are 11 divisions.

The word ``daffodil,'' however, has become so commonly used for species other than the long trumpet types that bulb catalogs and the general public have been using the names interchangeably. All daffodils are narcissus, but not all narcissus are daffodils. Narcissus is the family name.

Paperwhites.

Paper white narcissus (tazetta type) are native to the Mediterranean area and do not need any cold treatment to bring on blooms. They are best grown in decorative containers or shallow bowls without any drainage holes.

Place pebbles in containers (about an inch deep). Set bulbs on top, and fill in around them to hold in place. Add water until it has reached the bottom of the bulbs.

Put the container in a low-light spot for two weeks until growth starts. Then it can be moved to a sunny room. They will bloom eight to 10 weeks from the time of planting. Discard bulbs when they're through flowering - they can't be forced successfully a second time, nor are they hardy outdoors in frost areas.

Two other bulbs that can be forced without a cool treatment are Chinese Sacred Lily (Narcissus orientalis) and Soleil d'Or, which are yellow with a red center. Tulips, daffodils, hyacinths, and many of the minor bulbs need cool treatment before they can be forced indoors.

Light conditions.

Most all spring bulbs, including minor bulbs, will do well with a few hours of dappled shade. In fact, blooms last longer if they get relief from hot sun sometime during the day.

If you mix in a variety of other plants, make sure they like the same light conditions. For example, Crown Imperial (Fritillaria imperialis) might be a choice, because it is purported to repel moles and voles. But it does best and blooms better in full sun.