I just had a conversation with a customer about some plant that he wasn’t sure whether or not he should cut back. The plant turned out to me Mother of Thyme, and the answer is that it SHOULD NOT be cut back in the spring.
There are many different kinds of Thyme that we plant, but Mother of Thyme (Thymus serpyllum) is among our favorites. (On the plant maps we leave behind you’ll see it called MOT – our shorthand for a favorite plant.
Unlike the creeping thymes, MOT grows as a single plant. It is technically a zone 5 plant, which means that it has some winter kill in the zone 4 regions of the metro area, like Parker. So, in the spring, it’s really common to see a few dead parts of a MOT plant, but as a whole, the plants will generally make it and stay somewhat green throughout winter. It will root from branches that touch the ground, though it’s more common to see new plants emerge from seed.
This time of year, they’re starting to green up even more, and look a little more fresh. My mid-May, if you still see some dead patches, go ahead and cut those out of the plant.
MOT is sometimes called Wild Thyme, as this is the form it was first domesticated from.
There are literally hundreds of varieties of thyme you can plant in your garden. Most of them that we plant are some form of the Thymus serpyllum, such as the creeping thymes that we often put into walkways. The other common form of Thyme is Thymus vulgaris, commonly referred to as culinary thyme. This is a misnomer, as many of the serpyllums are also used for culinary purposes.