Answer: How frustrating! These dwarf morning glories (convolvulus) need full sun all day and an average soil to do their best. In my experience the most common limit to growth and good bloom performance is lack of sunshine and/or cool temperatures. The blooms are short lived, however they should be replaced quickly by oncoming flowers. The soil should be prepared initially by digging down and loosening it by about eight inches or more, and adding organic matter such as peat moss, compost, old rotted leaves, or aged stable manure and bedding. Basic soil tests would tell you if you need to add additional amendments such as fertilizer or lime. This plant does not require a rich soil, so it is possible you are overfertilizing. After planting, the soil moisture should be fairly even with the soil being slightly moist but not sopping wet. Several inches of organic mulch can be helpful in reglating the soil moisture level.
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