Answer: These plants do typically lose some of their interior leaves in the spring. A hard winter can also cause them to lose some additional leaves. This would be especially possible for plants set out in the fall because they lose moisture throught their leaves during the winter, but the new roots are not established enough yet to supply them.
These plants are sturdy growers and should be fine. With ouor dry spring this year especially they should be watered to keep the soil moist. Take care though not to overwater them. The soil should be moist, but not soggy. A weekly deep soaking plus a layer of organic mulch should encourage them to root deeper and be more drought resistant. Water them into the fall too as needed if there is no rain, check the soil with your fingers to make sure it is moist.
Once established, these are relatively drought tolerant plants.
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