Gardeners are optimists at heart.  They take a seed and plant it in some soil, or a wisp of plant material and coax it along in a pot of vermiculite and they wait patiently for the fruits of their labor.

But in the demo garden, this optimism has proven fatal for several plants.  A spell of mild summer weather or a bare spot that we can't ignore anymore, at we think that a plant will survive a transplanting in the middle of summer. We are, after all, Master Gardeners!

But, only the most attentive gardener should attempt this trick in the middle of the summer.  With transplant shock, drying summer winds, and several days of temperatures near the 100 degree mark, you almost need to stand over the poor little plants with a hose or watering can.

A little understanding of soil properties makes it clear why it is so difficult to transplant in the summer.  The mixture in most nursery plants is a fast draining mixture of sand, vermiculite, and peat moss.  This allows the nursery owners to water the plants often without keeping the roots too damp.

The surrounding soil in our demo garden and in most of Alameda County is clay.  The tiny particles in clay absorb the water from the quick draining soil mixture, and distribute it to other nearby clay particles.  Plant roots can use this water, but the plants in the newly transplanted plant are stuck in the now dry potting soil from the nursery. 

When the weather cools down, water evaporates less quickly and plants can hold on to the water already in their leaves and stems, while their roots can grow and seek water from the surrounding soil.

So from now on we'll just have to leave those spots bare, and ignore the pale pink penstemon next to the bright clashing orange coreopsis. We may even need to pass up the big sale at our favorite nursery.  The horror!

Check back next year, I'm optimistic we can resist our gardening impulses!