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How to Use Jobes Evergreen Fertilizer Spikes

Jobes evergreen spikes contain fertilizer that is slowly released into the soil around the evergreen. These fertilizer spikes last around 3 months before you will need to replace them. The benefits of slow-release, spike fertilizers are two-fold. You lower the risk of burning your evergreen through too much fertilizer applied at once, and you save yourself some time and effort--when you use these fertilizer spikes, you do not have to mix fertilizer and pour it around the plant.

Estimate the evergreen’s trunk diameter. If using these for a tree, you will need one fertilizer spike for every inch of trunk diameter, according to If you are using these spikes for an evergreen shrub, use one spike per 3 feet of height.

Place the spikes at equal lengths apart around the tree. You’ll be inserting the spikes at the drip line (where water runs off the outer leaves) of the tree and not near the trunk. If using these on a shrub, use a ruler to measure out 4 to 5 inches from the trunk/stem.

Place the spike point down and gently hammer it into the soil ( when you finish, the top of the spike should be below the top of the soil) with a mallet or hammer. If the ground is hard and dry, you may need to create a starter hole using a small hand spade.

Water around the tree or shrub, after inserting the spikes, to give the fertilizer a good start.

Fertilizer Spikes Work?

Fertilizer is important for most plants. It replenishes or adds nutrients and minerals to the soil and encourages vegetative growth or increased blooming and fruiting. Many contain formaldehyde, but others are completely organic. They are actually designed to be hammered into the ground. Although fertilizer spike manufacturers may claim that the spikes take the guesswork out of fertilizing, that claim is true only up to a point. The spikes work, but you still have to calculate how much fertilizer to use for your specific plants. In addition, the nutrients usually don't distribute evenly over soil, unlike liquid or granulated fertilizers when they are applied properly. When to fertilize a lawn depends on its type of grass. Cool-weather vegetables that mature quickly usually do not benefit from slow- or controlled-release fertilizers such as those in spikes, but warm-season crops can benefit from such fertilizers applied during planting time, according to a National Gardening Association website article.


Replace the spikes every 90 days (3 months) at minimum for best results.

Jobes offers several types of fertilizing spikes--evergreen fertilizer spikes have a formula best suited for evergreen trees and shrubs. Using other Jobes fertilizer formulas on evergreens may not yield desired results.

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