To start with, I want to let you know that I absolutely love the "This Old House" series! If I had Tivo, I would record every episode.
However, even with a show that is as highly liked and respected as TOH, there's some room for improvement. While watching this series, I have never found fault with any of the advice given by the series crew members but I do take issue with comments made during a recent episode (the ground cover segment on the TOH show televised on November 14, 2010). During the segment, in which Roger Cook was interviewing a nursery owner/operator regarding the use of grass replacement ground covers, the nursery owner recommended the use of various ground cover species, including periwinkle (Vinca minor) and English ivy (Hedera helix). Although the nursery owner mentioned that these two species can quickly expand beyond their original planting site, no mention was made of their real invasive potential. In truth, both of these plants are highly invasive, as they can displace native plants and should not be used as ground covers outside their own native habitats. There are plenty of available native ground cover species that would be perfectly suitable for any habitat and even though they may not possess the rapid growth and spreading habits of the non-native English ivy and periwinkle species, they are much less of a threat to native ecosystems. (Unfortunately, the characteristics that make these two plant species appealing to some homeowners also make these plants a threat to native plant ecosystems.) For those of us that are educated/trained in native plant ecosystems, we are quite aware of the native plant displacement potential of highly invasive plants such as periwinkle and English ivy. Our native plant communities would be much greater served if TOH's landscaping segments focused on the use of native plants and pointed out the inherent risks of using non-native invasives.