Although plastic mulch is helpful in keeping the weeds down, it just gets in the way of fertilizing and improving the soil. Next year, you might think about removing it and just using mulch. When you remove it, add some compost to the top of the soil, away from the trunk. That will help improve the dirt. For now, cut back some of the plastic around the base of the Hawaii Hibiscus so the fertilizer will come in contact with the soil and work its way to the roots. As for watering, how much depends on the amount of rainfall, temperature and wind. Generally, new shrubs need an inch a week. Our planting and care guide has great tips for keeping your plants healthy
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