Do I Really Need to Fertilize My Trees and Shrubs? Tips for Idaho Homeowners


If your trees and shrubs were like kids, you’d be feeding them all the time, just to stop the whining.

“Pleeaaaase, I need some fertilizerrrrrrrrrr.”

“I’m so hungryyyyyyyy!!”

“Why isn’t there any foooooooood?"

But your trees and shrubs, sweet things, just sit quietly and politely, never complaining, patiently waiting for you to feed them.

You feed them, right? Uh oh.

Fertilizing trees and shrubs is important, even though there’s no whining.

Check out these tips:

Why Fertilize Trees and Shrubs?

You look and feel better after a healthy meal, right?

Same with your Idaho trees and shrubs. Fertilizer gives them a boost that improves their health and appearance, from strong roots to glossy leaves to plentiful, pretty flowers.

unhealthy tree with disease needs fertilization

When your trees and shrubs struggle to get the important nutrients they need, they get weak. That makes them more susceptible to damaging insects and diseases.

Struggling trees and shrubs won’t grow as tall or as full as they could, either.

When Do I Need to Fertilize Trees and Shrubs?

You have a couple great choices. But there are times to avoid fertilizing, too.

Here’s a look:

Fertilizing Trees and Shrubs: Spring Feeding

You have to admit, winter is long here in Idaho and pretty much any plant emerging from its winter slumber could use a dose of fertilizer, including your trees and shrubs. Fertilize trees and shrubs in spring not just to help them grow and thrive, but to better stand up to attacks from diseases and pests.

Nitrogen is the key, so look for a high-nitrogen fertilizer with numbers like 4-1-1, 3-1-1 or 3-1-2.

Fertilizing Trees and Shrubs in Fall

Fall is a great time to fertilize trees and shrubs in Idaho. Why? A few reasons:

Give ‘Em a Root Boost

Your trees and shrubs usually soak up fertilizer and use it to put out new leaf growth. But in the fall, their roots take those nutrients and use them to boost their health, really soaking in the good stuff they need to thrive.

Tree roots and leaves

Fertilize Trees and Shrubs to Replace Nutrients

Summer is tough on your trees and shrubs. All that growing takes a lot out of them.

They’ve been busy providing shade, being home to birds and squirrels, producing berries for birds.

All that hard work uses up a lot of nutrients. Fertilize trees and shrubs in fall to replace them.

Fertilize for Fall Color

If you love those vibrant golden, orange, and crimson leaves, make sure your trees and shrubs are healthy enough to produce them.

When a tree doesn’t have enough nutrients, you can see it in weak, dying leaves — even before they have a chance to turn color and drift to the ground naturally.

If you notice yellowing leaves long before the fall color change, that’s a sign your tree is struggling and needs a nutrient boost. Fertilizing trees and shrubs delivers a long-lasting meal.

Fertilizing Trees and Shrubs In Idaho: Things to Avoid

  • Avoid Late Summer Nitrogen. Don’t fertilize trees and shrubs with high nitrogen fertilizer after mid-August. That late-summer feeding can cause some plants to put out a new flush of growth that could be susceptible to early frost damage.\
  • Don’t Fertilize New Trees and Shrubs. Newly planted trees and shrubs can’t absorb those tasty nutrients until they grow an adequate root system. So resist the temptation to feed those babies. It can actually prevent good root growth.
  • Avoid Fertilizing During Drought. Don’t fertilize trees and shrubs during the stress of drought unless you’re watering them regularly. They can’t use that fertilizer without enough water. Some fertilizers may actually damage the roots and scorch the leaves if water is lacking.

Fertilizing Trees and Shrubs In Idaho: Time for a Deeper Feeding

Sometimes your trees are Thanksgiving dinner kind of hungry.

Deep root tree fertilization injects nutrients for your tree directly deep into the soil, rather than spreading it over the top.

By injecting the fertilizer with high pressure, the nutrients can reach the deepest tree roots fast, feeding your tree from the roots up.

Tree injection

The fertilizer is delivered straight to the tree’s roots, with a long, cool-looking wand, so your tree gets an immediate nutrition boost.

Then, over time, the nutrients make their way to the rest of your tree, making it healthier and more vibrant.

How do you know if your tree needs this extra boost? Look for these signs:

  • Their leaves are smaller than normal.
  • Leaves have dead spots or are yellowing.
  • Branches are thinning, or the tips are dying.
  • There isn’t much growth.

Fall is a great time for deep root fertilizer in Idaho. The deep feeding will bolster your trees after the stress of a long, hot summer of growing, and set them up in good shape for the winter ahead.

Are Your Trees and Shrubs Ready for a New Best Friend?

Best friends bond over food — sharing snacks, inviting each other over for dinner, and splitting a Friday night pizza.

Lawn Buddies offers tree and shrub fertilization throughout the year with granular fertilizer, and liquid deep root tree fertilizer in spring and fall.

Both services are available for our Idaho Falls and Boise customers who use our full-service lawn care program.

That gives you extra peace of mind — choose an Idaho Falls or Boise professional lawn care service that bundles your yard’s most-needed treatments into one convenient, no-fuss plan, plus know your valuable trees and shrubs are getting the nourishing nutrients they need to thrive.

Got a few minutes? That’s all you need to get started.
Fill out the form on this page.
Call us at (208) 656-9131.
Or read more about our services.
Then kick back and relax in your healthy, thriving yard.

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Image Source: tree roots, deep root fertilization

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