Your serious gardener probably doesn't bother - too easy, too common, they grow in ditches by the side of the road, for heaven's sake! Gardening, like life, should be a constant struggle against the elements, insects, too-much or too-little hydration, and in-laws bearing petunias in pots, and bringing one's rare roses or orchids to flower year after year, with military precision and planning, apparently guarantees the thrill of victory.
I'd rather observe than battle. You see your life in the arc of one flower: the vigorous morning, opening to dew and hummingbirds and energetic growth; the afternoon sun and full flowering of your ambition and maturity; the gentle evening and its contented wilting and spent stamens; night-time, when you humbly fall to the grass and sleep. Your younger brother does the same the next day, and your nephew, your daughter, your third cousin twice removed. This daily miracle pleases me more than any prideful campaign of cultivars.