Weymouth, Mass. — The garden is a blaze of daffodils right now -- 163 by latest count -- and I have a Dutch bulb grower to thank for that. Meanwhile, the tulips are just beginning to open so that the early-spring color that began with the crocus in March will continue for a while yet.
My prime interest is food gardening. But I do enjoy seeing color in the front garden. In the summer it comes from easy-to-grow annuals, but more startling spring color comes from just-as-easy-to-grow bulbs -- daffodils, tulips, hyacinths, and the like. But it is the next few weeks, after flowering, that are the most important if your display of beauty is to be repeated next spring.
A still common misconception among many gardeners is that spring-flowering bulbs must be encouraged to die back as soon as they are done flowering. "Don't water them after the flowers die," I was once told. Nothing could be more wrong.
It was a chance seating alongside a bulb grower at a dinner in Amsterdam some years ago that put me on the right road to early-spring beauty. I was in Holland on a travel-writing assignment when I met Dick de Vrooman. Once I learned that he was a bulb grower, and he learned that my hands were in the soil more often than they were out on most weekends, we spent a delightful hour or so swapping ideas, most of them coming from him to me.
On bulb care his comment was: "The first six weeks after flowering are the most important in a bulb's life. It is then that the new bulb for next year is being formed. If you don't get good rains in this period, water well."
While post-bloom watering is important, it won't alone assure you of good blooms year after year. This, then, is the approach that has worked well for me , producing increasing quantities of large daffodils and tulips that stabilize after declining in size over the first two to three years.
[The effort of flowering apparently draws off somewhat more energy than the tulip can afford if it is to produce an equally large bulb. Some gardeners replant new tulip bulbs every year, discarding the old plants. For my part, once the tulip bulbs have stabilized they are still large enough and attractive enough to remain in the garden. I have tulips still flowering nine years after planting the original bulbs.]
* Mulch the bulbs. Good preparation starts the previous fall, when I mulch the bulbs with about 3 inches of shredded leaves (any other organic material will do). This not only protects the bulbs from heaving in rapid freeze-thaw situations, but it conditions the soil for improved growing conditions. The mulch remains undisturbed all year round but has almost completely rotted down by the time the next fall application comes along.
* In the spring -- after the new leaves have pushed through -- a fertilizer can be added, if you wish. Early fertilizing is considered best, but I have found it to be beneficial even if applied as late as when the flowers bloom. The suggestion that late fertilization can induce bulbs to break dormancy at the wrong time of year has not happened in my experience. However, don't fertilize after the bulbs have gone dormant.
* Cut off the heads of flowers the moment they have begun to die off and before the seed has started to form. This way all of the energy that would have gone into seed production the natural way will be diverted to the bulb.
* Water well during this post-bloom period if rainfall is not adequate. It is in this period that green leaves (including the green flower stalk) direct energy down into the forming bulb. The longer they can be induced to remain green, the more energy they will store in the bulb for next year's flower.
* Leave the withering green leaves on as long as possible. I hide them by planting flowering annuals in the bulb bed. Because I have a year-round mulch on these beds, I simply push the leaves under the mulch once they have totally withered away. This way they, too, help recharge the soil.
It is advisable to divide daffodils and hyacinths every three years, as the bulbs quickly double and triple up. I haven't done so for years, so in midsummer I will lift and gently divide them. If small bulbs don't come away readily from the larger parent bulb, leave them attached. They haven't yet been weaned, so to speak, an d need another year or so with the parent bulb.
I will replant the newly divided bulbs in the fall.