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Spring flowering bulbs, including such favorites as tulips and daffodils, are one of the signs that winter is over and are a true delight. While the bulbs themselves are nothing to look at, the flowers they produce come in all colors, and they really brighten the landscape.
Bulbs are underground storage structures that allow a plant to survive harsh climatic conditions. The wild forms of most of the winter-hardy, spring-flowering bulbs commonly planted by gardeners are found mostly in Europe and Asia, especially in Mediterranean countries, such as Spain and Turkey; Morocco in North Africa, and the Middle East. They are often found in areas with a Mediterranean climate: relatively wet winters, short springs, and hot, dry summers.
Technically, a bulb has specific characteristics. Similar structures (crocuses form corms, not bulbs for example) are sold under the general umbrella of “bulbs” because the care is the same.
Collecting bulbs from the wild is a good way to love something to extinction. The bulbs we sell are grown in nurseries, mostly in the Netherlands. The Dutch were a major maritime trading power back when “we” were still English colonies. The Dutch imported a lot of bulbs, cornered the market and got the industry rolling, and never let go.
The bulbs you plant in the fall flower any time from late winter to late spring, depending on the species and variety. A given plant flowers from about 10 days to a several weeks depending on temperature (the cooler the weather, the longer they last; hot, windy and low humidity conditions age flowers fast). Planting bulbs that bloom at different times gives you a full season of bloom.
When to plant?
I have found various rules of thumb. Bulb experts Brent and Becky Heath state: “Bulbs seem to perform better when planted in cool soil, so it is best to plant after you have had your first killing frost but before the ground freezes hard.”
Dr. Leonard Perry, University of Vermont, suggests planting when the soil temperatures are below 60 degrees Fahrenheit. That is going to vary with your location. In Beltsville, MD, that is about mid-October; in DC, it will be later, maybe October 31st. It’s a balancing act between a lot of factors: when you have time; the ideal time to plant; the aging (drying out) of the bulbs as they sit on the store shelf or in your home. We recommend buying bulbs early while the selection is good, and setting them aside in a cool, dry spot until you are ready to plant.
While there are shade-tolerant bulbs, for the most part, they are best in a sunny spot in good quality soil that drains well after rain.
In digging to plant bulbs, the bottom of the hole should be 3 to 4 times the height of the bulb. If the bulb is 1 inch tall, the bottom of the hole should be 3 to 4 inches deep.
If planting a new area, you should prepare a bed for the bulbs by digging and loosening the soil to a depth of about a foot. Get some bags of Leafgro (commercially-composted leaves and grass clippings from Maryland Environmental Service, available at Behnke’s). Spread it out over the loosened soil, about a 3 inch deep layer would be good. Mix this layer into the soil with your shovel or turning fork tool. This is best done when the soil is moist but not muddy.
Remove enough of your “improved” soil so the bottom of the hole is at the right depth for the bulbs, and sprinkle a bulb fertilizer like Bulb Tone, per bag directions, on the soil that is still in the hole. Place the bulbs, preferably in random drifts instead of rows, on the soil, then cover them with the remaining soil.
Tamp the soil down to remove big air pockets (tamp: slap the soil with the back of the shovel). Water the area gently to settle the soil. This is best done with a watering can or a hose with a breaker (a nozzle that gives a gentle watering like a watering can. The most essential garden tool you can own, in my opinion.)
Note that planting bulbs is simple, not necessarily easy!! There’s a difference. Any gardener will tell you, probably to the point that you start looking for an escape route, that the key to successful gardening is good soil, and the best way to get good soil is to work compost into the soil. Wait, don’t run away!!
Got deer, squirrels, or other grazers or four-legged bulb or flower thieves? Click here for more about Critter-Resistant Spring-Blooming Bulbs.
by Larry Hurley