Fertilizing Rose of Sharon

Roses of Sharon are famously tough, adaptable shrubs that seem like they would not like being babied with fertilizer, but is that true? Should you fertilize your rose of Sharon? If so, at what point in its growth? Can you overdo it? 


How to Fertilize Rose of Sharon

Starting from the ground up, rose of Sharon prefers a neutral to alkaline pH soil. If you’re not sure of your garden soil composition, you can find home soil tests at nurseries and hardware stores or send a sample away for a thorough test through your county’s agricultural extension office.

Rose of Sharon shrubs are not heavy feeders, meaning they need little extra nutrition beyond a layer of compost for mulch. At planting time or in spring of its first year, you can add some slow-release fertilizer, which should carry your plant through the season. The best fertilizer formulation would be one offering a balanced ratio of nutrients or with a slightly higher phosphorus level – the P in “N-P-K” ratio on the product package. Note: formulas with a higher nitrogen (N) level will spur leaf growth at the expense of flowers.

In containers, since nutrients wash out with watering, you might consider following up with a diluted liquid fertilizer at half the strength recommended on the label. 

Roses of Sharon will indicate they are being fed too rich a diet with yellowing or browning leaves. 

Best Time to Fertilize Rose of Sharon

The main time to fertilize rose of Sharon shrubs is during its first year or two in your garden as it becomes established. Spring is ideal for starting with a granular formula that will release nutrients for several months. 

Containers may want a boost of liquid fertilizer perhaps monthly at half the label strength.

You can improve the soil by adding organic matter such as compost in the fall, which will improve the soil’s health over time. 

Best Fertilizer for Rose of Sharon

An ideal fertilizer would be a slow-release formula with a balanced composition, such as 10-10-10 or 14-14-14. The second number, phosphorus can be higher than the rest, but a higher nitrogen level is not recommended. 

 Rose of Sharon Fertilizing Tips

  • Fertilize lightly in the first year or two with a balanced, slow-release fertilizer.
  • Containers may benefit from a dilute liquid fertilizer monthly from spring through fall.
  • Overfeeding can result in yellowed or browned leaves.


-Always wear protective gloves and a face mask when handling chemical fertilizers.

-Closely follow all directions and storage guidelines that are on the fertilizer label.

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Author Erica Browne Grivas - Published 1-25-2022