Unwlecome in the Cold Frame

In our climate, cold frames are useful, but not as much as they are in places with milder climates. If they are in the sun, you cannot leave plants in them in winter, because temperatures in the frames can fluctuate enormously. They stay buried in ice and snow for most of the winter. However they are especially handy in spring.

Unexpected Invader

We are all familiar with foreign plants that do too well when they are brought to a new continent. It is the case of our native fireweed (Chamerion angustifolium) in the UK, and of the numerous European plants (often medicinal in origin) such as plantain (Plantago major) and coltsfoot (Tussilago farfara) which are completely entrenched in North America.
Sometimes though, a foreign plant will grow or only manage to survive, but it then becomes invasive in some circumstances. It seems to be the case with the cowslip.

Cowslip (Primula veris)

NARGS

The acronym NARGS stands for the North American Rock Garden Society. This year the General Annual Meeting of the Society is in Ann Arbor, Michigan. The meetings include among other things visits to some of the best local gardens. Here are three beautiful gardens I visited today with the group.