So, grass was never successful in our north-facing front yard here in Vancouver, so after our reno in 2018 we decided to try something different, and on a whim we planted random patches of irish moss (Sagina subulata 'Verna'), scotch moss (Sagina subulata 'Aurea'), and micro-clover (Trifolium repens var. Pipolina). The micro-clover was a mistake - it needed to be mowed and was always trying to infiltrate into the moss - but it all looked great: That's what it looked like in June 2022. Unfortunately, 2 years later the moss was almost all dead. We're not sure what caused it, but it was always hard to work out how much water it needed, and we think a couple of very hot summers were too much for it. I also found this page recently, which claims irish moss only has a 10 year life span. We'd like to try again, but want some advice first. The yard is directly north of the house, so about 2/3 of it gets full sun and 1/3 only morning/evening sun. The bushes lining the sidewalk are lavender (Lavandula x intermedia 'Provence'). They are still doing fine. Is irish moss a good idea for this? Will it always be a struggle to keep healthy? Will it only last 10 years even if we keep it alive? Is there a better 3rd plant? Any help would be greatly appreciated.
If the lavender is doing fine it might be too dry and sunny for any moss. It also depends on the soil -- if it's clay it might be too heavy, but usually lavender doesn't do well in clay around here so I bet it's not. Do you walk on the front yard at all, or let pets onto it? If you do, then I'd try creeping thymes: lemon, silver or regular. They and lavender like similar light and soil, they don't grow very tall, and they have flowers bees like. They can also be walked on. If you don't walk on it, how about some spreading low sedums? You can get leaf colours/variegations with various flower colours, and different heights and sizes/shapes of leaf.
If that space was mine, I'd mound the soil up several inches and place 3 g00d-sized, interesting rocks here and there (making sure to bury about 2/3 of the rock to make them look natural). Then choose a focal point shrub or tree like a weeping Japanese maple next to the largest rock. It should be off-centre, perhaps in the shadier area. Then choose a small variety of other low-growing, evergreen plants plants such as heathers, hellebores, small hostas and small grasses that can go in the sunnier or shadier part of the space. They should all have similar water requirements. Plant at least 3 of whatever you choose. The mosses can fill in the spaces between other perennials. Try to vary the textures and leaf colours of the plants you buy and consider what time of year they bloom. Also, when you're finished and happy with the placement of everything, put an attractive mulch over the soil to keep weeds at bay.
