Alstroemeria ‘Summer Relieve’ has been a real star in our trials. This patch is now 3 years old, and consists of 9 original plants. Flowering typically starts for us in early May, slows during the worst heat of summer, and picks up again as temperatures cool. Hardiness Zone 5b-8b.
It fascinates us that such a widespread native like Eustoma exaltatum isn’t more widely grown in gardens. Often known by the common names prairie gentian or lisianthus, eustoma is prized by flower arrangers, but not gardeners. Eustoma is native from coast to coast…Florida to California, and north to the Canadian border in Montana.
In the wild, Eustoma exaltatum is a short-lived perennial that can also behave as a biennial or even an annual in some sites. The key is to plant it where it can happily reseed as we have done in our gravelly crevice garden, which is odd, since in the wild, they are found in moist meadows and streamsides.
Below are our plants in peak flower now, during the brutal heat of summer. So far, we’ve struggled to keep this happy in a container, in the hopes we could make this available, but we continue to try.
Commercially, eustoma has been hybridized ad nauseam to create better cut flowers, but these hybrids seem to have lost all of their perennial nature compared to the wild genetics. Our plant pictured below is the large (2′-3′ tall) subspecies russellianum from wild collected seed from Bastrop County, Texas.
For years, we struggled to grow the Mediterranean/Balkan native spurge, Euphorbia characias…until we discovered its secrets. First, it isn’t a long lived plant to begin with…in most cases 3-5 years is it, so you’ll need to plant it where it’s likely to reseed. That would be well-drained slopes that are either mulched or covered with gravel.
Secondly, after it flowers in spring with its stunning show of yellow flowers, remove most of the flower stalks as soon as flowering has finished, except those needed to produce new seedlings (the flowers are also great to use in floral arrangements). If not, the seed stalks use up energy causing the plant to decline much faster. We’ve now allowed this to seed throughout the slopes in front of our house, and here is the result…a smattering of 3′ tall x 3′ wide clumps, photo taken mid-winter.
Although this section of the garden, planted in compost-amended sandy loam is irrigated, we typically don’t recommend irrigation for this spurge without excellent drainage. You’ll also read on-line that Euphorbia characias doesn’t like hot, humid summers…another example of fake gardening news that just keeps getting repeated without any concern for the facts.
We’ve also found Euphorbia characias to grow well in part sun under large trees, which keeps the soil dry. The plants will never be as dense as they are in full sun, but they survive and flowers. There is really not anything else that gives you this evergreen blue color and form in the winter garden.