American Witch Hazel Shrubs grow best if they are fertilized once in the spring and again in early summer. Hamamelis virginiana favors nutrient rich soil and ample fertilization. When selecting a fertilizer for your Witch Hazel, use a balanced fertilizer blended specifically for shrubs such as Espoma Tree Tone for example..
Either chemical fertilizers or organic matter can be used on American Witch Hazel Shrubs successfully. Since an organic method of applying manure and/or compost around the roots, produces excellent results and also improves the condition of the soil, this would be an excellent first line of attack. Organic additions to the soil can also be combined with a shot of chemical fertilizer for maximum effect.
Apply an early spring fertilizer with a product such as Espoma Tree-tone or Plant-tone at the recommended rate this will give the plant a boost of nitrogen that will be needed for healthy abundant foliage. Follow this up with a early summer application of Espoma Flower-tone, this will provide the necessary nutrients and raise the acid level in the soil which mahonia favor. Espoma products are easy to use, just sprinkle around the base of the plant and water it in. Be careful with products such as miracle-grow as these products can burn newly planted plants when not used at the recommended rates. Slow-release fertilizer can help prevent rapid sucker growth that is vulnerable to diseases and insects.
If you choose to use chemical fertilizers on your American Witch Hazel Shrubs, applying a slow-release, balanced fertilizer once a year in the spring is probably the simplest solution. There are many slow-release fertilizers on the market. If you can find a fertilizer formulated for shrubs and trees, this fertilizer would work well on Hamamelis virginiana. However, slow-release is certainly not the only way to fertilize Witch Hazel such as American Witch Hazel Shrubs although truth be told I feel its the best. A less expensive fast release fertilizer such as a 10-10-10 will work just as well if applied twice during the summer. If you are looking for a fertilizing routine tailored to your specific conditions, a soil sample should be taken and the fertilizer and trace elements matched to the needs of your soil.
Don’t fertilize American Witch Hazel Shrubs after August in the North. Fall is the time for Witch Hazel to begin preparing for dormancy even though they will be flowering soon. Fertilizing at this time may stimulate new growth that will be too tender to withstand the winter. In the South, a late summer into September application would be about right. As mentioned one spring application of a balanced fertilizer should more than suffice.
The amount of chemical fertilizer used per plant will vary with the size of the plant and it’s root system. Over-fertilization can be much more detrimental than under-fertilization. “Fertilizer burn” can occur when too much fertilizer is applied, resulting in a drying out of the roots and damage or even death of the rose.It is much, much better to err on the side of too little fertilizer than too much. When roots are burned, the first sign is often scorched looking leaves. If over-fertilization is severe, the plant may just wilt and die.