In order to promote plant growth, experts recommend that gardeners spread a generous amount of mulch around the plants to inhibit weed growth. Accordingly, the director of Sunlight Community Garden instructed volunteers to use plenty of mulch in their yearly landscaping, and the volunteers enthusiastically used up all of the available mulch. Nevertheless, plant productivity later fell somewhat.
Which of the following, if true, most helps to explain why acting on the experts’ recommendation failed to achieve its goal?
【选项】
Some of the plants that Sunlight Community Garden grows are vegetables that have excellent flavor but are not very hardy.
选项是否正确？