I have been experimenting with troughs on a sunny porch, since the rest of my yard has been decimated by an exploding deer population. Since a majority of plants suitable for a trough are better acclimated to an alpine climate, it's been a pretty rough go given our summer heat and humidity. But over the past few years, I have a number of successful tough plants that appear to be thriving. But I'm new to trough gardening and have a number of questions. The soil I've been using is about 1/3rd clay pebbles (meant to serve the same purpose as gravel, but lighter so the troughs can be moved more easily), 1/3rd coarse sand and 1/3rd coarse bark-based soilless potting mix. I know most of these plants thrive in a lean soil, so I don't fertilize and I haven't been amending the soil in any way. Should I be fertilizing or amending the soil annually? One of my dianthus (D. grationopolitanus Nyewood Cream) has formed a dense cushion 10 inches across and is nearly occupying the entire trough. Seems happy, though a very shy bloomer. Maybe a little fertilizer would boost the bloom? Should it be repotted? Also I am aware that many of alpine plants need to avoid winter wet. A couple weeks ago, I moved some troughs under an awning so they receive no rain at all but due to the low angle of the winter sun, they're still getting full sun. But I looked at the troughs today and they are bone dry. The plants still look fine. Does avoiding winter wet mean no water at all? Or should I water them sparingly maybe once a month over winter? Any advice would be well-appreciated!
