Answer: Surprisingly, these are not heavy feeders. If you are using an organic mulch several inches deep over the root area and they are growing well you may not need to fertilize at all. Ideally you would run some basic soil tests and fertilize if a need is shown for it by the test results. Otherwise you could use a general purpose slow release fertilizer such as Hollytone per the label instructions. Since you have already fertilized with something, you probably do not need to do so again this year.
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