How to Fertilize Leaves for a Magnolia Tree
- 1). Prune off any branches affected by fungal disease. Look for signs like spotted leaves (leaf spot), cankers on bark (nectria canker) or matted fungal thread (leaf blight). Dip a pair of bypass shears, lopping shears and a pruning saw in a mixture of 70 percent denatured alcohol and 30 percent water. Cut branches at a downward, 45-degree angle next to the tree collar.
- 2). Dilute a quick-release fertilizer with a NPK of 4-3-4 according to the manufacturer's directions. Fill a bucket with the amount of water indicated and add the liquid fertilizer. Pour the mixture in a spray bottle and attach it to the garden hose.
- 3). Wrap plastic around the base of the tree to prevent the fertilizer from splashing the base. Spray the fertilizer around the tree. Remove the plastic and wipe off any sprayed leaves with a towel.
- 4). Fertilize your tree every three to four weeks. Keep up the schedule to help aid the tree from succumbing to fungal disease.
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