Dear Garden Coach: I have several clumps of Iris that have not bloomed since they were planted over two years ago. They get full sun in morning and I used Earth Doctor fertilizer to see if this would help them bloom, and it did not.
Dear Joanne: I hear your frustration about wanting flowers and getting only green leaves.I am providing you with some general information from the American Iris Society for growing bearded Iris.
Iris grow best in a slightly acidic (pH of 6.8) well-drained soil. If your soil is heavy clay, you will want to amend it with compost or gypsum. Watering should be deep and infrequent; how often will depend on how well your soil drains. Remember that clay soils retain moisture longer than a sandy soil.
You mentioned your Iris is planted in full morning sun. They need at least six hours of direct sunlight (not shaded by trees). You also mention using Dr Earth Fertilizer. I am not sure which one you used and when your fertilized. The Rainbow Iris Farm recommends fertilizing in spring with bonemeal superphosphate, or a fertilizer low in nitrogen such as 6-10-10. Nitrogen is the first number and the second two are phosphorus and potassium. These are key nutrients for root and bloom production.
According to the Iris Society, a common mistake that inhibits flowering is planting the rhizomes too deeply. When planting, the roots should be placed in the planting hole and the top of the rhizome should be above the soil line. Do not mulch with organic matter because it creates shade on the rhizomes and excess moisture that causes them to rot.
Dear Garden Coach: What is happening to my African Daisy and this little ground cover? I have them planted in a couple of different spots in my garden, and after this last cold snap and rain they seem to have just curled up and died. As you can see, the ones that are in more sun look fine.
Valerie Kells, Concord
Dear Valerie: The fluctuation of temperatures is probably confusing to some of the plants. Arctotis ‘Pink Sugar’ (African Daisy) and ground cover, Teucrium cossonii, are plants that love hot, dry conditions. From your photos, It looks like the ones that are stressed are in a shadier spot, and most likely that in combination with wet, cold and heavy clay soil have caused the problem. Wait until the temperatures warm up a bit, then cut back where there is new growth and move the plant to a sunnier location.
One of the best practices any gardener can do is to walk around their garden at different times of the year and note what plants might need to be moved to a different spot in the garden. Now is a perfect time to see how your plants are growing during this very chilly early spring, and note which spots are in deep, cold shade. Late summer is also a good time to note whether there are plants getting too much sun.
Published at Tue, 06 Mar 2018 20:07:27 +0000