Have you noticed how some plants don’t stay in one place?
Take ground cover plants for instance. You put them in a nice spot, well away from anything else, and admire your new acquisition. For the next few days, not much happens. If you remember, you check on it again in a couple of weeks. Has it got bigger – difficult to tell. Three months later and it’s on the move. Two years down the track and you’re probably tearing out handfuls and regretting ever having put it anywhere near your garden. Sometimes the centre dies out (as with euphorbia robbiae), leaving a mass of plant with a proverbial polo mint space in the middle.
There are also plants that spread by underground stolons. A stolon is a prostrate stem, at or just below the surface of the ground, that produces new plants from buds at its tips or nodes. This can be worrying as you can’t see how far the plant is spreading (unlike the runners above ground a plant such as a strawberry produces). But in the case of lilium nepalense, new plants are a cause of excitement and celebration. Four years ago, I planted three bulbs of this lily. It can be a bit tricky to please, needing an acid soil in a cool, moist spot in shade, with an open, humus-rich soil. It also needs to be kept drier during the winter which can be tricky with our predominantly wet winters. It does not take well to pot culture as the stems run around underground before coming to the surface, not appearing until June. Nor will it tolerate much in the way of frost. Four years later and my three bulbs have produced seven stems.
These grows up to three feet tall, then large hanging buds form before opening to pale yellow flowers with large maroon throats. These are so heavy the stems can bend and snap under the weight.
This lily is definitely a prima donna, but if you can please it, it will run around, popping up all over the place. Long may it continue.