Last week I visited with the Desert Gardeners Club in Carson City. I asked the gardeners to give me some ideas for articles. Donna wanted to know how to grow hydrangeas in our area. Hydrangeas are beautiful plants with large deep green leaves, which sometimes provide red fall color. They have spectacular flowers that can be long lasting, even holding their beauty when dried. Some flowers are large balls. Others look like halos of lovely blooms. Some are the size of dinner plates.
Sadly, hydrangeas like a rich porous soil, something few of our yards have. Our soils are often clay with poor drainage or sandy with little moisture-holding capacity. Whether clay or sand, these soils are rarely rich in organic matter. Our soils are usually alkaline with a pH above 7. Because of the high pH, if hydrangeas grow at all, they are likely to have pink or red flowers, rather than the often-desired blue. Blue flowers only develop when soils are acid with a pH below 5.5.
With the intense sun and wind of Northern Nevada, both summer and winter, hydrangeas will need partial shade and wind protection or they will burn. Most need moist to wet soils, not our droughty soils. Many are high humidity tolerant, but few are low humidity tolerant. Most are cold tolerant.
Are there varieties of hydrangeas that will grow here? Yes. Will they thrive? Rarely, under average garden conditions. Are they adapted to our drought conditions, both winter and summer? No. They are marginal plants for our climate, except in very special yards that have optimum conditions. They will usually need special care and attention, lots of water, good drainage and sun and wind protection, winter and summer. For most of us, hydrangeas might be better choices for large containers that can be moved in and out seasonally.
If you are passionate about hydrangeas, you can get them to grow. If purchasing them, try to find varieties that will tolerate your soil type, low humidity and drought. For example, Hydrangea paniculata, ’Little Lime,’™ from Wayside Gardens (online) is said to be drought tolerant and tolerant of poor soils. You may be able to get appropriate varieties locally at our better nurseries.