Planted behind the bird bath from my husband's paternal grandmother with a sunflower sculpture my uncle made from scrap iron and spark plugs (those are the petals), is Oenothera speciosus 'Rosea,' Showy Pink Evening Primrose.
The write up about it in the catalog said, "A heat loving plant that thrives in sunny, dry areas along baking south and west facing walls and pavement areas. Spreading rapidly on shallow roots, give this beauty plenty of room to grow or it will overrun smaller, less vigorous plants."
The catalog was right. It spreads. Not really a problem where I have it because it is growing along our neighbor's fence which has a concrete base. The other plants in the area are hollies, a mugo pine, a forsythia, and the tall salvia from our amazing gardening neighbor. However, it is now creeping in to the path along its bed and trying to encircle some mums I transplanted this spring.
It has shallow roots. When it shows up someplace I don't want it, I pull it out.
It's just starting it's big showy bloom, but will bloom some all summer.
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