Fertilizer spikes can harm and even kill trees if used incorrectly. Driving fertilizer spikes into the ground too close to a tree’s trunk can cause the tree to die. Additionally, using too many fertilizer spikes can overload the soil with fertilizer, which causes the tree to dry out and die. Finally, using fertilizer spikes on only one side of a tree can cause uneven root growth that causes the tree to become more likely to fall over and uproot itself. With the right know-how, you can prevent all of these dangers and use fertilizer spikes effectively.
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Are Fertilizer Spikes Good for Trees?
Fertilizer spikes can be extremely beneficial for trees. Most trees do not require large amounts of fertilizer, so the slow release of nutrients as a spike breaks down helps to provide a trickle of extra nutrition that fuels healthy tree growth. Granular and liquid fertilizers designed for grass and garden plants quickly work their way into the soil. This quick influx of nutrients can increase the risk of fertilizer burn for trees, so spikes are often a good choice for trees.
- Fertilizer spikes are often very good for trees.
- Because fertilizer spikes break down slowly in soil, they provide nutrients over a longer time period than other fertilizers.
- Use this soil testing kit to determine if your soil is lacking nutrients that can be supplied by fertilizer spikes.
Before using fertilizer spikes, it is a great idea to perform a soil test with an at-home testing kit. This will allow you to see what nutrients your soil is lacking, if any. Then, based on the results of the test, you can choose the right fertilizer spikes. This allows you to use fertilizer spikes when you need them and avoid spending money on spikes if they’re not necessary.
3 Ways Fertilizer Spikes Kill Trees (and How to Avoid Them)
Fertilizer spikes can be harmful to trees if used incorrectly. Before you pound tree fertilizer spikes into the ground, review these dangers and learn how to prevent them from killing your tree.
The Spikes are Too Close to the Tree
Fertilizer spikes driven into the ground too close to the tree’s trunk can kill a tree. You can physically damage roots by driving in a fertilizer spike, which in turn invites deadly plant diseases and insects to attack the tree. Plus, placing fertilizer too close to the trunk encourages roots to grow in the nutrient-rich soil near the tree trunk. By putting spikes too close, you discourage your tree from spreading wide roots that help it resist drought.
- Using fertilizer spikes too close to a tree’s trunk can kill your tree.
- Roots can be damaged by fertilizer spikes, which invites disease and harmful insects.
- Fertilizer spikes close to the trunk encourage poor root development that makes trees susceptible to death from drought.
- Fertilizer spikes should be driven in at the edges of your tree’s branch canopy.
To eliminate the risk of damage from fertilizer spikes, drive them in at the “drip line” of the tree. The drip line is the edges of the tree’s branch canopy, where rain water drips off the tips of the branches. The tree’s roots will spread toward the spikes, to absorb the nutrients in the soil there. This creates a wide network of supportive roots for a healthy tree.
There are Too Many Spikes
Overfeeding your tree with too many fertilizer spikes can overload the soil with nitrogen. This dries out the soil and can even pull water out of the tree’s root system. This dehydration results in “fertilizer burn,” which is signified by dry, brown leaves that fall off the tree. For young trees, this can be deadly. Although overfeeding your tree with too many fertilizer spikes at once is the most common cause of death by fertilizer burn, using fertilizer spikes too frequently can also kill trees.
- Using too many fertilizer spikes at once can kill a tree through fertilizer burn.
- Fertilizer burn dehydrates the soil and the tree, which can cause leaves to fall off and kill the tree.
- Use 1 fertilizer spike for every 2 inches (5 cm) of your tree’s trunk diameter.
- Wait at least 6 months between fertilizer spike applications.
Prevent overusing fertilizer spikes by using 1 spike for every 2 inches (5 cm) of the tree’s trunk diameter. Use calipers or a similar tool to find your tree’s diameter. If it is 8 inches in diameter (20 cm), use 4 fertilizer spikes. To prevent overuse, allow at least 6 months for fertilizer spikes to break down before adding new ones. Most trees benefit from fertilizer spikes if they are used 1 to 2 times per year.
Spikes are Placed too Close Together
Concentrating fertilizer spikes on one side of a tree can cause poor root growth and kill your tree. If you continually place fertilizer spikes on one or two sides of the tree, the roots will grow only in this direction. This makes the tree much more likely to fall over in the direction of the increased root growth, since there are fewer roots on the other sides to hold the tree in place. This risk of a fallen tree can be harmful to your home, fence, or other structures. It will also kill the tree.
- Continually using spikes on 1 or 2 sides of a tree leads to uneven root growth that can kill a tree.
- Tree roots grow toward fertilizer spikes.
- If the spikes are all placed on one side, the roots will grow in this direction, which can make the tree unsteady and likely to fall.
- Use fertilizer spikes evenly on all sides.
- For young trees that only need 1 spike, use a spike on a different side of the tree every 6 months.
Pound fertilizer spikes into the ground evenly around the tree’s drip line to prevent uneven root growth. If you are using multiple fertilizer spikes, drive them into the ground on all sides of the tree. If your tree is so small that it only requires 1 fertilizer spike, add a new spike on a different side of the tree every 6 months. This will encourage even root growth in all directions.
Can You Use Fertilizer Spikes in Potted Trees?
It is not advisable to use fertilizer spikes for potted trees. Because the pot is usually narrower than the tree’s canopy, the spikes will have to be placed too close to the trunk. This can harm the roots and cause the tree to weaken and die. Additionally, potted trees can be grown in a controlled environment. So, you can provide quality nutrition by using a good potting soil. This renders fertilizer spikes unnecessary.
- Do not use fertilizer spikes for trees grown in containers.
- Pots do not allow enough space for you to place fertilizer spikes at the correct distance from the tree’s trunk.
- Pot your tree in high-quality soil to provide adequate nutrients.
- For an extra boost, use this slow-release granular fertilizer that won’t burn your potted tree.
If you still wish to fertilize your potted trees, it is best to use types of fertilizers other than spikes. An organic, slow-release fertilizer is the best choice. Slow-release fertilizers only provide nutrients when they are required by plants and soil microbes, which drastically reduces the risk of fertilizer burn.
Do Fertilizer Spikes Damage Trees?
Fertilizer spikes are generally beneficial to trees but can be harmful if used improperly. Here are the dangers and how to avoid them:
- Fertilizer spikes driven into the soil too close to the trunk can cause tree disease and death.
- Using too many fertilizer spikes can kill trees through fertilizer burn.
- Placing fertilizer spikes on 1 or 2 sides of a tree causes uneven root growth that can cause trees to fall over and die.
- Drive in all fertilizer spikes at the edges of the tree’s branch canopy.
- Use 1 fertilizer spike for every 2 inches (5 cm) of your tree’s trunk diameter.
- Allow 6 months between fertilizer spike applications.
- Spread fertilizer spikes evenly around the tree.
- If you are using a small number of fertilizer spikes, alternate the placement of the spike(s) every 6 months.
By following these tips you can avoid all the dangers of fertilizer spikes and benefit from the positives. Whether you are encouraging mature trees or developing a newly planted tree, fertilizer spikes can help you grow the healthiest tree possible.
