I have five Black Bamboo plants spaced out in an (approx. ) 3 feet wide by 18 feet long (4feet in depth) container. The tallest culms are about 12 feet now. Someone told me that the bamboo should be fertilized in Sept. or Oct. with a high nitrogen grass fertilizer and again mid-March. Also that I should mulch with mushroom manure over winter. Is this correct information? If so - how much fertilizer and manure should I use. I am hopeful that the bamboo will get taller next year and fill out to make a good screen against the neighbours' tall house.
Bamboo belongs to the grass family, and are heavy feeders. Like lawn grass, however, their roots can be damaged by applying too much fertiliser. The dictum I follow is "small quantities often" There must be many bamboo growers who swears by their ferlisation regimen. However, what works for any gardener must be influenced by his/her garden's soil condition, what climactic condition exist, what material is available easily and ecoomically, and whether the bamboo is a clumper or a runner. But here is what I do for my running bamboos. I put down the first application of fertiliser at the end of March, early April with nitrogen number between 10-15, whatever is lying around. I continue to fertilise once every 4-6 weeks, using half of the recommended application rate for the product I use. When the first shots start to show, I switch to a high nitrogen fertiliser (usually, whatever I use on the lawn in the summer), and continue to use this until August, when I switch to low nitrogen fertiliser (something like 5-10-10). However, I never use high nitrogen fertilisers in the first year of a new planting. I arbitrary stop fertilising when the day time temperature drops to below 15C consistently. Mulching is important - bamboos grow best with a constantly moist (but well drained) soil. Mulching with an organic material is very beneficial - hence, the application of spent mushroom manure annually in the spring. If you are gardening in a very cold region or if the soil surface is bare, an additional application of manure mulch in the fall will be beneficial and definitely wouldn't do any harm. I aim for about a 2 inch thickness of mulch. The culms have a high silica content. Using the leaves as a mulch is beneficial - they are a good source of silica. Afterall, this is what happens in nature.
Thanks Weekend Gardner...I too was wondering about fertilizing some P. atrovaginata that I have just planted (about 2 weeks ago). Probably just fertilize the yard, or take the fertilizer back as it is 'fall/winter fertilizer.'
Hardy plants, including lawns generally benefit most from fall fertilization. To make better targeted applications sample your soil and have it tested.
