Powell Gardens’ Greenhouses each have a purpose in production and / or winter storage of unhardy plants in our collection. Greenhouse #1 is our “cool” greenhouse with low nighttime temperatures; it is a place to store warm temperate plants that require climates milder than ours but still are not tropical. Plants from deserts and Mediterranean climates (including California) or semi-tropical climates like the Gulf Coast or Southern Japan and China thrive in this greenhouse and usually relish being outdoors for our hot summers.
A peek in the door will reveal our collection of succulents from around the world. Most of these plants go on display outdoors around the Visitor Center in summer.
The bougainvillea is beginning to bloom and these dazzling floral beauties thrive in cool winter conditions. We have several and they go on display in containers or in the conservatory at other seasons when they are in peak bloom. Bougainvilleas like lean soils so be sure to not over-fertilize them or you will get all foliage and no flowers.
The Loquat (Eriobotrya japonica) that bloomed last fall is starting to form fruit that will ripen this spring. Loquats are fruit trees native to Southern China and Japan and our tree will go on display in the Heartland Harvest Garden for the summer. Loquats must have a cool but not frigid winter and thrive outdoors on the Gulf Coast or California. They make a beautiful container plan here!
Plants like this Chinese Redbud (Cercis chinensis ‘Don Egolf‘) are also spending the winter in Greenhouse 1. It is spring in the greenhouse and the redbud is in full bloom. This new cultivar of redbud is listed as zone 6 and was donated to us as a small plant. We will plant it on the grounds next spring–many plants gain hardiness as the plant gets more size. This new cultivar was bred by its namesake at the National Arboretum and its “attributes” are that it is a large shrub and sets no seed pods.
This green spiny shrub is a seedling of Hardy Orange (Poncirus trifoliata) that we grew from seed donated by the Missouri Botanical Garden. These hardy oranges are scheduled to be planted in the Heartland Harvest Garden where they will make an impenetrable hedge. Hardy orange has wonderfully fragrant flowers typical of all Citrus and sour “mini orange” fruit that can be concocted into a preserve that is edible. They are an important understock (roots to graft onto) for other varieties of citrus to improve hardiness. We do have an established ‘Flying Dragon’ cultivar of hardy orange growing outdoors on the south side of the Visitor Center.
Many of our stock plants of salvia spend the winter in greenhouse 1 and bloom beautifully in the shorter days of winter. The purple salvia is the cultivar ‘Paul’ and the vermilion cultivar is ‘Orange Louie.’ Both of these salvias go on display in the Hummingbird Garden for the summer.