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How to Use Tree Spikes

By Jenny Harrington ; Updated September 21, 2017

Fertilizer spikes are compressed rods of fertilizer that are driven into the ground around trees to provide nutrients to the soils. They break down slowly, releasing a steady supply of nutrients. They are more expensive than granular fertilizers but are also more convenient to use. Spike varieties are made for general tree use, or there are types specially formulated for the specific type of tree. Using fertilizer spikes correctly is key to getting the proper amount of nutrients to the trees roots in a usable form.

Push the plastic cap, included with the tree spikes, onto the blunt end of the spike. Plastic caps are reusable so there are more spikes than caps in each package.

Set the point of a spike into the ground at the distance from the trunk recommended on the fertilizer spike packaging. Drive the spike into the ground using a rubber mallet until the plastic cap is just above the soil level.

Pull the plastic cap off the spike. Finish driving the spike into the soil until it sits 2 to 4 inches beneath the soil surface.

Place the cap on a second spike and drive it into the soil. Use the amount of spikes recommended on the package for your tree type and size, spacing them equally apart around the tree.

Water the tree thoroughly after installing the spikes. The spikes will slowly dissolve in the soil and leach the nutrients to the tree roots. Replace them as recommended on the spike package.


Things You Will Need

  • Tree spikes
  • Rubber mallet


  • Save the plastic caps from each package of spikes you purchase. The caps may crack or break so having extra caps from past packages is advisable.
  • If you have trouble driving the spikes beneath the soil surface, push them down with the mallet handle or another narrow object.


  • Spikes do not evenly distribute fertilizer. Use traditional granular fertilizers if trees are under stress from lack of fertilizer.

About the Author


Jenny Harrington has been a freelance writer since 2006. Her published articles have appeared in various print and online publications. Previously, she owned her own business, selling handmade items online, wholesale and at crafts fairs. Harrington's specialties include small business information, crafting, decorating and gardening.