Forsythia_DBG_2764Just when you don’t think you can stand another minute of bare branches or dead, brown-gray foliage, spring heralds its arrival in a burst of dazzling yellow. All over town, forsythias reassure us that the growing season has finally arrived.

Originally from eastern Asia, where they have been cultivated for centuries, forsythias were collected for western gardens in the early 1800s. Most current garden varieties are hybrids of two species, Forsythia suspensa and F. viridissima. The problem is that the resulting cultivars aren’t reliably hardy in much of Colorado.

Happily plant breeders have been hard at work. ‘Northern Gold’ and ‘Northern Sun’ are both the product of a cross that includes a very hardy (but not very showy) Korean species. The resulting bushes retain the spectacular floral display of their other parentage, and survive down to USDA zone 4, or even 3 with a thick mulch or good snow cover. That’s plenty of hardiness for the Front Range. ‘Meadowlark’ is another cultivar hardy to zone 4.

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iris.jpg“Bloom events” is a term used by biologists, phenologists, and other plant scientists when they discuss when plants bloom. And this year, they must be noticing several weird bloom events occurring in our area!

As most of you know, we’ve just gone through a very very dry winter. Yes, drier even than normal for here. As (seemingly) the rest of the country had record snow accumulations, we had one of our driest winters on record. Add to that the fairly warm winter temperatures along with plenty of spring wind and you’ve got gardeners scratching their heads as some of their hardiest plants have disappeared while wimpier (or so they thought) plants have come through unscathed. (more…)

What plant thrives indoors, shrugs off low humidity, and blooms all winter in bold shades of white to pink to red? Surprise! It’s wax begonias!

Also called fibrous begonias, these familiar bedding plants have large, round succulent leaves in either lime green or a beautiful burgundy- or bronze-red. Flowers have fleshy petals surrounding a bright yellow cluster of stamens. Plants grow to a height of about six to twelve inches. They tend to flop, creating a solid mass of color, and even trailing over walls and container edges.

Wax begonias are usually considered summer annuals. It’s true that they do well in our gardens, given light shade or (preferably filtered) sun. Space them a foot apart in soil high in organic matter and keep the roots evenly moist. Happily, pests are usually not a problem—even the deer tend to leave them alone! (more…)

With giant, trumpet-shaped flowers facing outward around a central stalk, a blooming amaryllis makes an eye-catching houseplant. Colors range from white through pink to red (and even almost black), as well as salmon-orange. Stripes or contracting edges are common. “African” amaryllis have more compact forms suited to indoor cultivation. Dwarf amaryllis are smaller in size but can produce more blooms.

Not surprisingly, these striking, easy-to-grow bulbs are popular holiday gifts; perhaps you received one this year. There’s even a bright red variety named “Merry Christmas”!

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