Doris Duke\u20141912-1993\u2014was a millionaire heiress with multiple homes, a colorful personal life and a peripatetic nature. Whenever she touched down in New Jersey, she came to rest at Duke Farms, a property established by her father in the state\u2019s central region. In Duke\u2019s time, the mammoth greenhouses at Duke Farms contained a series of themed gardens full of plants grown to perfection. Among those perfect specimens was a magnificent Plumbago auriculata, commonly known as plumbago or leadwort, trained up a wall. I saw it in full bloom, covered with flower clusters containing hundreds, if not thousands of individual blue blossoms. I fell in love.
\nTheoretically, it is just as easy to fall in love with an undemanding plant as it is to lose your heart to a demanding one. In reality, though, the demanding ones often have the greater allure. In cold winter climates, plumbago falls into the demanding category. It must be grown in a container and does best in a greenhouse. If your greenhouse is spacious, like Doris Duke\u2019s, you can let the plant grow to the large dimensions it attains in the wild–up to seven feet tall and ten feet wide. If you do not have a greenhouse, your potted plumbago will probably grow to a more reasonable three feet tall and wide, still big enough to require a substantial container. If you are not muscular, you should have some hired muscle on hand twice a year, because the plant will have to be hauled outside to spend the late spring and summer months soaking up sun and hauled back inside with temperatures drop.
\nIs all this effort truly worth it? Many people think so. The common auriculata species, which originated in South Africa, is evergreen, with three-inch dark green leaves. The plants can be trained up a support structure, as at the Duke estate, but can also be pruned to keep them shrubby. The foliage is attractive, but it is the phlox-like flowers that grab your eyes and heart. They are sky blue, without a hint of the purple tint that you often find in so-called \u201cblue\u201d flowers. They bloom freely under good conditions, covering the plant with clusters of five-petaled blooms.
\nAt my house, I am the one who does the hauling twice a year and I think the effort is worth it, even when I have to resort to a few aspirins to diminish back pain after the move.
\nPlumbago was officially discovered in South Africa in the eighteenth century. The \u201cplumb\u201d in the plant\u2019s botanical name comes from the Latin word \u201cplumbum\u201d, for metallic lead, which, when freshly mined, is blue-white in color. The same root is used to describe people who work with lead pipes\u2014plumbers\u2014and plumb lines, lead-weighted cords used to establish straight lines in construction.
\nHappy plumbago plants require well-drained soil and warm temperatures. They bloom best during the warmer months, with growth slowing down in winter. During that time, watering and fertilization should also slow down. If you have a mature plant, prune the branches back by at least one third every year, to maintain shrubby growth. At the end of winter it also pays to take the plumbago out of the pot to see whether it has become pot-bound. If the roots have enveloped the surface of the root ball, either repot in a larger container or prune the roots by shaving the bottom two inches off the root ball and reducing its overall diameter by two inches. Repot using fresh soil. Water thoroughly and feed using a balanced fertilizer according to package directions.
\nLarge retail greenhouses sometimes carry plumbago. The \u2018Imperial Blue\u2019 variety features flowers that bloom in a deeper blue shade than those of the species. The plant wholesaler, Monrovia, offers a cultivar called \u2018Monott\u2019, with larger flower clusters. \u2018White Cape\u2019 is a white-flowered plumbago, also known as Plumbago auriculata alba. Monrovia used to offer it, but I did not see it in their most recent catalog. This is probably because most plumbago buyers lust after blue flowers.
\nDoris Duke\u2019s magnificent plumbago has probably gone the way of her greenhouse display gardens\u2014dismantled years ago in favor of Duke Farm\u2019s new ecologically-focused mission. However, those of us who don\u2019t mind putting in a little effort can still avail ourselves of the richness of blue plumbago.
\n\u2018Imperial Blue\u2019 is available from Logee\u2019s Greenhouses, 141 North Street, Danielson, CT 06239; (888) 330-8038; www.logees.com. Free catalog.<\/p>\n","protected":false},"excerpt":{"rendered":"
Doris Duke\u20141912-1993\u2014was a millionaire heiress with multiple homes, a colorful personal life and a peripatetic nature. Whenever she touched down in New Jersey, she came to rest at Duke Farms, a property established by her father in the state\u2019s central region. In Duke\u2019s time, the mammoth greenhouses at Duke Farms contained a series of themed … Read more<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,6,2,3,5],"tags":[150,274,1278,1277,1280,1279,1282,1281],"class_list":["post-1442","post","type-post","status-publish","format-standard","hentry","category-fall","category-general-interest","category-spring","category-summer","category-winter","tag-blue-flowers","tag-container-gardening","tag-doris-duke","tag-duke-farms","tag-house-plants","tag-plumbago","tag-south-african-plants","tag-tender-plants"],"_links":{"self":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts\/1442","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/comments?post=1442"}],"version-history":[{"count":1,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts\/1442\/revisions"}],"predecessor-version":[{"id":1443,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/posts\/1442\/revisions\/1443"}],"wp:attachment":[{"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/media?parent=1442"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/categories?post=1442"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gardenersapprentice.com\/gardeningtips\/wp-json\/wp\/v2\/tags?post=1442"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}