How to Grow Oenothera Grandis
- 1). Choose a location for your primrose that will get at least eight hours of full sunlight each day and has sandy and well-drained soil. Plant seedlings after the last threat of frost is past.
- 2). Test the soil before you plant your primrose. The pH should be between 5.5 and 7.0. Lower the pH if necessary by adding 0.8 lb. of elemental sulfur for every 100 square feet of soil. Raise the pH by mixing 2 inches of peat moss into the top 6 inches of soil with a tiller.
- 3). Dig a hole at least 6 inches deep, using a trowel.
- 4). Remove the primrose seedling from its nursery pot. Place the plant into the hole. Refill the hole with native soil and pack it gently.
- 5). Water the seedling with 1 to 2 inches of water after planting. Apply that same amount of water every week during the dry months.
- 6). Remove the stems after the flowers bloom to prevent seed production.
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