Thursday, February 26, 2009

Little Spring Bulbs Make their Appearance

Spring has certainly sprung at Powell Gardens with the blooming of the early small bulbs. From crocus to snowdrops, winter aconite and dwarf iris; there is a rainbow of flower color hugging the ground. The best displays are located on the Island Garden and in the Rock & Waterfall Garden.


Early honeybees relish the bright golden flowers of Golden Bunch Crocus (Crocus flavus) on the Island Garden.

A clump of Gipsy Girl Crocus (Crocus chrysanthus) on the Island Garden is much paler yellow with purple stripes on the underside of the flowers. The Island Garden is out of reach of most squirrels so we can display a good variety of crocus there (Squirrels think crocus corms are little candy treats!)

"Tommy" Crocus (Crocus tommasinianus) show themselves in the Rock & Waterfall Garden. This garden is set in a native woodland and full of squirrels--Tommy crocus are resistant to squirrels.

A closer look at Tommy Crocus--this may be the cultivar 'Lilac Beauty' as we have planted mixes.

Snowdrops (Galanthus elwesii shown) are in full bloom on the Island Garden but the best displays are in the Rock & Waterfall Garden. This small bulb carpets many areas of the Rock & Waterfall Garden and each year we divide them out (just after bloom) to increase our plantings.
Winter Aconinte (Eranthis hyemalis shown) are also beginning to bloom. They have been self-sowing wherever planted. Best masses are along the upper walk in the Rock & Waterfall Garden.
Katherine Hodgkin Dwarf Iris (Iris histroides hybrid) is already in bloom on the Island Garden. There are many dwarf iris in colors from deep indigo to yellow that will soon be in bloom.
A view of Katherine Hodgkin Dwarf Iris from above: the aqua blue color of this cultivar is quite distinctive.
Some of the first "wildflowers" are also in bloom but they are very tiny! This is a little speedwell (Veronica sp.) in the buffalo grass on the Island Garden. Speedwell is considered a lawn weed but its flowers are such a treat for early spring
The Korean Azaleas (Rhododendron yedoense var. poukhanense) are in bloom in the Conservatory's Fragrance Display. This is a very good species of azalea for our climate and it has very nice, delicate fragrance.
Wednesdays high of 69F pushed many of the spring bulbs into flower and although cold is predicted for the weekend all the bulbs that have emerged are adapted to such setbacks. Over the next few weeks the early spring bulbs will delight visitors to the gardens. Come out and get a preview of spring!

Thursday, February 19, 2009

Cool Greenhouse #1

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.

A mist bench in Greenhouse 1 is a place to root cuttings of many of our specialty or stock plants. You can see cuttings of Viburnums just beginning to bud in the foreground, variegated schefflera in the middle and cuttings of magnolias towards the back. The brown mat you can see on the right is a heat mat that gives the trays of cuttings warmth to encourage root growth.
Flats of specialty plants we grew from seeds or cuttings fill available space. The "spiky" plants are a tray of Red Yucca (Hesperaloe parviflora) that we grew from an exceptionally hardy plant. Left are thriving cuttings of our groundcover Memorial Rose (Rosa wichuriana) from the Perennial Garden: destined for our Spring Plant Sale the first weekend in May. The back right plants are seedlings of buckeyes; both bottlebrush and red that will be used to beef up our collections.
Last is a seedling of a rare Missouri tree: Littlehip Hawthorn (Crataegus spatulata). This seedling will be destined for our collections as it gains some size. It has tiny red hips in fall that birds relish and some of the most beautiful fluted and cinnamon-silver mottled trunks of any plant hardy here.
Powell Gardens is completing two recycled greenhouses (from the former Longview Gardens) and still plans to assemble one more recycled greenhouse (donated from a local landscaper) to store the unhardy plants of the Heartland Harvest Garden. When all greenhouses are complete, Powell Gardens will have 10 greenhouses for production of seasonal plants and storage of its collection of over 15,000 accessioned plants. Keep watch for opportunities to visit them, as they are not open to the public except for special events -- maybe next fall 2009?

Monday, February 9, 2009

The Season of the Greenhouse

'Tis the season of the greenhouse! More than 1,000 varieties of plants have been ordered and sorted for sowing and growing in the Powell Gardens greenhouses. For the next 3 months the greenhouses will be rockin'! The new Heartland Harvest Garden has added more than 350 seasonal edibles and vegetables to the process.

The greenhouses look empty to begin the season, but as the seedlings get transplanted and spaced they will soon be bursting at the seams. Already trays of seedlings remind me of Midwestern fields.
Flowers produced for color and fragrance in the conservatory display are really starting to sing. This is a true red Ranunculus sometimes called Persian Buttercup. Ranunculus are one of our favorite cool season flowers for use in containers; just 5 short weeks until we begin putting cool season flowers outdoors.
This beautiful and extremely fragrant Primrose (Primula acaulis) is the new cultivar 'Pageant Salmon.'
Osteospermums (African Daisies) are another favorite cool season flower; this is the cultivar 'Lemon Symphony.'
The Primroses actually come in almost all colors from red to yellow and almost blue in this mix. The warmer colored flowers seem to be more fragrant.
Ranunculus also come in a kaleidoscope of colors including this nearly true violet seedling.
This little green "nubbin" in the greenhouse is a new fruit of a MANGO! We are carefully watching how our new dwarf, grafted mangoes fare and whether fruit will be produced and ripen through our hot summers in containers outdoors.
Our coffee plants our doing well, too. We formerly had some large specimens that outgrew our greenhouses. We were successful in flowering and fruiting our old plants. Coffee flowers are white and intensely fragrant, the ripe fruit are red and of course it is the seed "bean" inside the fruit that is dried and ground to make coffee. These plants will go on permanent display in the Heartland Harvest Garden's greenhouse.
The new growth on the purple podded variety of cacao (Theobroma cacao) has beautiful pink new leaves. If you don't know cacao, it is the plant that flowers on its trunk to produce acorn squash-shaped pods that contain the seeds from which CHOCOLATE is made. We have three varieties of cacao and all are doing better than I expected. It is a fussy plant demanding heat and high humidity.
We can't wait to share 2009's crop of plants with Powell Gardens' visitors. As long as Mother Nature cooperates, we'll start planting the outdoor beds at the Visitor Education Center on March 16. Yes, there is a whole host of plants that like it cool and can tolerate frosts. The Heartland Harvest Garden won't open to the public until June 14, when all our interesting tropical food plants will go on public display.