The graceful magnolia species of trees provides beauty and stability for landscape gardens across America, but particularly in the warmth of Southern states. Grandiflora, stellata and virginiata are popular species of this versatile group. Provide your magnolia tree nutrients by fertilising regularly, and it will reward you with vigorous growth and a bounty of beautiful blooms.
Perform a soil test. Kits are available through garden centres or your county extension office. Follow test recommendations for rates of application or check the results with the extension office.
Fertilise magnolia trees when they are dormant. Winter months, typically December through February, are preferable.
Choose a complete granular fertiliser, such as 12-4-8, unless soil testing reveals a deficiency in for a particular element. The numbers of the fertiliser correspond to nitrogen, phosphorus, and potassium, all essential elements for proper magnolia tree health.
Use a broadcast spreader to evenly distribute the fertiliser over the planting area. Cover 1 1/2 times beyond the canopy line on the ground to reach the entire root zone.
Apply the fertiliser when the ground is dry, then water well to soak the granules into the root zone.
Avoid over-fertilisation. Check yearly for signs of yellowing leaves, poor growth, or a reduction in blooms before performing a soil test, and only add fertiliser if a deficiency is evident. Adding too much fertiliser, or applying too often, can stunt growth or severely damage a magnolia tree.