不能由花粉繁殖。opens 指“带来”下面一个很矛盾的状态：生到这世上就有苦难，但我们又在享受生命。至于怎么翻译全句就要诗人来了。
见植物学解释：Flowers with extra petals are mutants. Wild-type flowers are singles. A mutation in the genes of these can lead to double blooms. In terms of typical evolution, this mutation does not give a plant an advantage. The extra petals develop from the reproductive organs, so double blooms are typically sterile. They can’t reproduce.
Since they don’t have pollen, double flowering plants tend to stay open longer than single flowers. It is as if they are waiting for pollinators that just aren’t coming. The showiness of the double petals, plus the longer bloom time, has made these mutants desirable for us in the garden.
Read more at Gardening Know How: What Are Double Blooms: Understanding Flowers With Extra Petals https://www.gardeningknowhow.com/ornamental/flowers/fgen/what-are-double-blooms.htm
