Sweetly scented white blossoms appear intermittently year-round and set thin-skinned lemons.
The ASPCA lists lemon, lime, orange and grapefruit as toxic to cats and dogs, and to horses. The fruit itself is fine to eat; the trouble is the peel, leaves and stems, whose oils can cause vomiting, diarrhoea, listlessness and skin irritation. A Meyer lemon is not listed by name, but it is the same genus, so keep peel, prunings and fallen leaves away from pets.
For gardeners who like to stay ahead.