Hello,
My garden is located in north east Toronto near Markham. It has clay soil and seems compacted.
I planted two heart leaved asters side by side three years ago. They have let out stalks to bloom every year, but this year, one of the plants have not. The leaves have come back but no stalks have emerged to produce buds. What could be happening? The other plant seems fine and has grown out stalks to bloom.
I have also planted a patch of obedient plants three years ago and they have been fine until this year. They seem to have heights in ascending order with one side of the patch having short stalks and then the heights increase in the middle with end of the patch having normal height. What could be the problem there?
The top leaves of the stalks seem to have curled in a weird manner and other leaves of the plant seem to have bites from Japanese beetles. Another thing is that invasive clover ground cover and native wild strawberry have grown at the base of the obedient plants, could that be the problem?
What can I do for these plants? Thank you for your insight and help.
I suspect that you may have answered your questions in the the second sentence of your post, where you say you have compacted clay soil.
Heart-leaf aster “prefers light shade with partial sun, moderate moisture, rich soils, such as found in open woods or wood edges.” That definition and more information about this plant, can be found here. Obedient plants have very similar requirements.
Clay soil, especially compacted clay soil, is not rich in organic matter and will be slow to drain. With the excessive rain we have had, this may be why your plant is struggling. And, yes, there can be slight differences in the soil texture around neighbouring plants, which I suspect accounts for the varying heights of your obedient plants, if they are all receiving the same amount of light.
For success with your garden, you really need to deal with the soil issue, amending it with organic matter. Please review our Gardening Guide on Soil Fertility.
As for the other issue, Japanese beetles are a challenge indeed, but they are usually not very fond of Obedient plants, as noted in this study. Have you seen and clearly identified Japanese beetles on them? See images here. (Note that the chemicals described in that publication are NOT used here in Ontario.) If so, then please refer to the response we have another inquirer about managing an infestation.
The other pests that impact obedient plants are aphids and spider mites, which are also pretty recognizable. Spider mites can cause cupping of the leaves, as seen here. If you think these may be the culprits, please use the search box on our site to find advice we have provided other inquirers.
And, if it turns out that the insects on your plants are none of the above, please repost your question with photos that show the damage and the insects and we’ll be happy to respond.
Finally, too much water can also cause plants to wilt, leaves to droop and seem distorted, which brings us back to the subject of the soil condition.