Posted on Friday, January 01, 2010 by admin in Care |

The landscaping season is just getting under way in and around the Capitol. A favorite spot of mine is the Tulip Library, a neat garden located between the Tidal basin and the Jefferson Memorial. There are about 100 small beds, each planted with one to two hundred varieties of tulips, most of them samples of the tulips that bloom around town. Early this month you may still be in time to see some of the lovely little species tulips that have been planted there this year for the first time at the recommendation of Rob DeFeo, chief horticulturist for the National Park Service. Species tulips come back in my garden, along with the tall tulips that the squirrels steal and bury in the pachysandra, but other tulips rarely bloom a second time for me. As I understand tulipology, after they bloom, the mother bulbs of the big beautiful Dutch tulips make bulblets instead of making flowers for next year’s blooming.

The flowers in the Tulip Library always look gorgeous, so I asked Rob the secret of his success, expecting to lectured about adding humus and a fall fertilization. Rob’s answer surprised me. The beds are rototilled in the fall, he said, and tested for nutrient deficiencies. If none shows up, Rob doesn’t add anything ( he just has the beds rototilled and plants the bulbs four to six inches deep for species tulips, and four to eight inches deep for the big tulips. I was pleased to learn, by the way, that these tulips are no more sacrosanct to squirrels than yours or mine. The only way the Park Service can be sure of saving the bulbs from the little darlings is to cover the beds with wire mesh that is removed when the tips begin to come up in spring.

Rob’s advise to us is: never fertilize without knowing what the need is, only fertilize to replace a nutrient that is in short supply. The Park Service apparently considers runoff of fertilizers potentially as destructive to the Bay as pesticides, so they are used only when really necessary. “No farmer plants without running a soil test, and he does it every year.” Rob said he’s tried putting bonemeal into a tulip planting hole to see if it makes a difference, and he said he didn’t see any special benefit. Rob said the Extension Services at the state university will test your soil for you. You also can buy soil testing kits that will report on the presence of the primary nutrients nitrogen, phosphorous, potash (NPK). Local nurseries I am sure, sell pH testing kits for something under $18. And for about $31, you can buy a kit that tests the NPK as well as the pH.

The Tulip Library’s season in the sun is short, but the 14,000 trees on the Capitol grounds, and in the parks around DC, are always there, and always worth a visit even after the cherry blossoms go by. These great woody plants are among the most complex organic structures on the planet and those in DC are always in extraordinarily good condition. The huge old trees here on the Hill have deeply fissured bark and gnarly limbs and some have been here for a century and more. The National Park Service takes their trees very seriously indeed, and now that funds are short, they’re interested in donated trees. The program that accepts donations is called `Blossoms in Our Future,’ and over 1000 trees have already been donated to DC by people from all over the world. Many contributions to buy cherry trees have come from tourists from Japan, who visited when the cherry trees originally donated by Japan were in bloom. Others come from people interested in having a tree planted in someone’s memory. Donated trees are numbered, and a central data base records the names of donors, those to whom the trees are dedicated, and where the donated trees are located. The cost of donating a tree is $250, and donors receive certificate of appreciation as well as a map showing location of tree donated.

Another interesting perspective on the use of fertilizer came from Wally Reed, a horticulturist at the US Botanic Garden. I asked him about the height and the brilliance of the six-foot foxgloves and the delphinium that were so prominent in the delightful `Charlotte’s Web’ exhibit which has just ended. Wally told me they are a cultivar named `Foxy’. I thought I’d written `Foxy’ up in The American Horticultural Society Flower Finder Book as a dwarf of Digitalis purpurea. I looked it up, and by golly, it is! So how come a dwarf is a six-foot giant, all whistles and bells? (One of the less entertaining aspects of being an author is that your mistakes are recorded in print in long lasting books!)

So I called the DC Village, which is the Botanic Garden’s growing facility, and contacted the gardener who grew those spectacular plants, Debbie Went. “It’s `Foxy’ all right, “ said Debbie, “and the delphiniums are the Pacific Giant strain.” Reluctantly, she told me her grower’s secret: the plants were started last fall, grown in cool greenhouses so they developed very slowly over many months, and at the same time they were kept on a constant-feed fertilizer program. In other words, we’d never see foxgloves or delphiniums like that in our back yard even if we stood on our heads to get them going unless we lived in the cool Pacific Northwest, or in New England.

But constant feeding can have a place in our plants lives, Wally suggested. He said to see what happens when you use a tiny bit of a high nitrogen liquid fertilizer, such as 20-20-20, every time you water your plants as a foliar feed. He said almost any annual will respond to that treatment with lush (if not six-foot) growth, and mentioned impatiens, petunias, and salvia. He also said `Miracle Grow’ fertilizer could be used.

And by the way, have you visited the brand new gift shop at the Botanic Garden? It opened mid March, and is staffed by the fund-raising branch of the Botanic garden, the National Fund for US Botanic Garden. They are something of a parallel to FONA, Friends Of The National Arboretum. The group was recently authorized by Congress, and their primary aim is to get together the funds needed to begin work on The National Garden which will some day grace the blunted wedge that occupies the space beyond the Botanic Garden west wall between Independence Avenue, Third Street and Maryland Avenue. Ground breaking is hoped for late this year or early 1997.