It is December and finally winter has arrived in Denver! Who hasn’t noticed the low winter light catching the grasses and adding a glowing soft orange to the otherwise monochromatic landscape. Perhaps now is the time to dream of growing grasses or sedges in your own unique space.
Grasses are adept at growing in different environments within the city. Read labels carefully so as not to buy a “cool season” (perennial here) whose growth, or requirements, do not meet your needs. There are many cool season grasses that may take a few years to reach their maximum height (some formidable!). Also, establish that you are not buying a self-seeding variety if you want control. Also, check the details and ascertain that the water requirements can be met. Remember even the most water frugal plants need help to establish.
Also, consider if you would like “warm season” (annual here) grasses too. I bought a beautiful Red Fountain Grass Pennisetum setaceum at the CSU Extension Plant Sale, which is still pretty in December snow. This annual could have been overwintered indoors, but I took the lazy route and I like the golden winter interest that remains.
Grasses are invaluable in restricted spaces. For example: rooftop gardens can be made into wonderful living areas with miniature grasses like a Hybrid Idaho Fescue Fistula ‘Siskiyou Blue”, or perhaps a sedge like Ivory Sedge Carex eburnea. Or large grasses can make dramatic modern statements. The delicate structure of grasses contrasts beautifully with concrete or other urban materials. Also, the narrow leaves are tolerant of high winds and brutal summer roof-top temperatures. If you are using pots I would consider wrapping containers in burlap or another insulating material during the winter.
Some cool season grasses that fill in small space front garden varieties include: Dwarf Fountain Grass Hameln Pennisetum alopecuroides ‘Hameln’ and Atlas Fescue Fistula mairei. These make great border plants . For more dramatic focal point grasses the CSU Extension has a wonderful list to gather more comprehensive ideas as you dream for next year. CSU Horticultural Extension: Ornamental grasses information and list of plants.
If you have the luxury of more land and you would like some self sowing varieties the Indian Rice Grass Achnatherum hymenoideds looks lovely in the low winter light. The now wintery soft brown Blue Grama Bouteloua gracilis (our state grass!) is a casual signature planting that spreads prodigiously, and helps make the winter Western landscape warm and magnificent.
Some large grasses can get messy in the wintery weather but there is a solution if you don’t wish to cut back in fall or winter. Gardener Dave wrote a good piece in the Jeffco blog about controlling tall grasses, through the winter, so that they stay attractive and can then be left for cutting back until spring Click here for large grasses that can be maintained as structural interest in winter.
Anne Beletic CMG