Denver Botanic Gardens recently installed four solar-powered atmospheric water harvesters – three at York Street and one at Chatfield Farms. Using the power of the sun, these SOURCE units accelerate the condensation process to convert water vapor into water.</p> All but one of the harvesters, which are made by Phoenix-based Zero Mass Water</a>, are helping irrigate plants. The other offers visitors to the York Street location the opportunity to take a taste! Each SOURCE will generate between five and seven liters each day (not quite two gallons), storing up to 30 liters (almost 8 gallons) each in a built-in tank.</p> This is one example of many partnerships the Gardens has with entrepreneurs as well as government and corporate entities to showcase and test water-efficient innovations. These are the first SOURCE units to be incorporated into irrigation. The Gardens is showcasing this technology as a potential solution to growing vegetables in areas without reliable fresh water supplies.</p> Here is more information on other Gardens water-efficient partnerships, programs and initiatives</a>.</p>
Mirroring the natural alpine and woodland habitats that the Rock Alpine Garden is inspired by, spring is a great time to walk through this garden. Both alpine and woodland plants bloom early in the year in response to the physical restraints of their native environments.</p> Alpines are programmed to bloom as soon as the snow melts in their native environments. Plants you might find on Loveland Pass or Trail Ridge Road blooming in late June or July bloom in Denver in April.</p> One of the best areas to see true alpines in the Rock Alpine Garden is the crevice garden on the south side of the main path — Draba</em>, Potentilla</em> and Erigeron</em> bloom in tight north facing crevices. Additional areas to see true alpines are in the various troughs scattered through the garden — Silene acaulis</em>, Polemonium viscosum</em>, and Hymenoxys grandiflora</em> should flower by the end of the month. The north side of the Cactus and Succulent house is another great place to focus on the early flowers of Draba</em> from Eurasia, and the mat and cushion forming plants that creep and crawl amongst the rocks.</p> One of my most favorite “secret areas” in the Rock Alpine Garden is the far southern path that takes visitors along the far southern edge of the garden along the perimeter fence. It passes through some of the best woodland areas in the rock garden. Take time to enjoy the full variety of plants in the densely-planted area. If one enters the path near the crevice garden at the east entrance near the South African Plaza and you continue on this path, it will take you into more woodland areas of the rock garden which rarely get the visitation they deserve. Passing down a slight slope take in the various Lenten roses (Helleborus</em>) and woodland sweet peas (Lathryus vernus</em>) along the path.</p> A spectacular show awaits visitors in the far southwest corner of the Rock Alpine Garden along the stucco wall at the boundary with the neighbors. Here a beautiful display of Helleborus</em>, Corydalis</em>, wind flowers (Anemone</em>), bloodroot (Sanguinaria</em>) and violets (Viola</em> odorata</em>) create a tapestry of color in April. Many woodland plants are programmed like alpines to bloom during a short season. Unlike plants high on top of a mountain which are delayed until warm temperatures melt the snow, woodland plants bloom in early spring before the trees above leaf out and block out the sun. This means the woodland areas are at their best in April as well.</p> I hope you can make it to the Rock Alpine Garden in the month of April. While you are at the Gardens make sure and check out the alpine section of the Mordecai Children’s Garden</a> — it should be in prime color as well.</p>
Visitors walking in the Gates Montane Garden may notice something strange through late spring: black velvet bags on the tips of one tree near the Cheesman Park gate. It is not trash or a new art installation — the Gardens' horticulture staff is attempting to propagate the tree, a bigtooth maple, which has recently come under attack by our local squirrel population.</p> The bigtooth maple Acer grandidentatum</em> is a Colorado native that thrives in dry conditions and tolerates heavy soils much better than other maple species. It’s a smaller tree that can have either a tree-like or shrub-like form and has excellent fall color.</p> This specific tree was collected near Logan, Utah because of its good fall color and more tree-like form. In an effort to save the genetics of this tree from marauding squirrels, we are using propagation techniques pioneered by researchers at Utah State University. This species is usually very hard to propagate by cuttings, but by placing dark bags over the stems, the tree is forced to grow in darkness — a process called etiolation. Cuttings taken from this etiolated growth root much easier than cuttings taken from stems that grew in full sunlight. The bags will be removed after the tree begins growing in late April or May.</p> If successful, the propagated clones of this tree will be planted in other locations at the Gardens. Perfecting vegetative propagation of bigtooth maple will allow us to provide trees with a predictable habit and fall color, since trees grown from seed take a long time to grow and can be very variable in their appearance.</p> If this experiment is successful we hope to propagate more bigtooth maples in the future to make them available at the Grown at the Gardens division of the Spring Plant Sale.</p>
