15 Common Gardening Mistakes You Should Avoid

Take note of how to save your plants from the common blunders we all make.

overwatering

Every gardener who has ever planted, pruned, or watered a plant has at some time in their life done it the wrong way – even me, the Grumpy Gardener. Making mistakes is just part of being human. The trick is learning from each and every mistake.

The following list of 15 gardening goofs, gaffes, and blunders is by no means comprehensive. There are plenty of other ways to show the world that you don't know what you're doing. But these are some of the more basic and common errors. So if you don't want your neighbors thinking of you as basic and common, don't make these mistakes.

01 of 15

Overwatering Your Plants

plant watering

The Result: The plant turns yellow, drops leaves, rots, or simply croaks.

Giving a plant too much water kills it faster than giving it too little. Although most plants prefer moist soil, they don't like soggy, poorly drained soil. Waterlogged soil keeps roots from functioning properly. Because of this, overwatered plants may wilt on a sunny day from too much water, not too little.

To lessen your chances of overwatering, keep track of what you water, so you don't water the same plant three times a day. Separate plants that need lots of water from those that need just a little. Before you water, stick your finger about an inch deep into the soil near the base of the base to see if the soil is moist or dry.

02 of 15

Planting Too Deeply

planting deep in soil

The Result: The plant's roots smother and the plant slowly dies.

Roots need air to breathe. They can't get it when they're buried 6 feet under. So when you plant a tree or shrub, make sure that the top of the root ball is slightly higher than the surrounding soil. To keep air from drying out the root ball, cover the top with and inch or so of mulch.

03 of 15

Overfertilizing

fertilizer

The Result: Your plant grows too fast, refuses to bloom or fruit, becomes susceptible to disease, and may suffer fertilizer burn. Excess nutrients pollute ground water and streams.

Fertilizer is not "plant food." Fertilizer contains chemicals that enable leaves to make food from sunshine. Plants growing in fertile soil that contains lots of organic matter do not need frequent fertilization. Plants that are dormant or suffering from drought need no fertilizer at all.

Buy fertilizers formulated for your types of plants and apply at the rates specified on the label. Choose organic, slow-release fertilizers that work slowly over months at a time and actually improve the soil by adding organic matter.

04 of 15

Not Reading The Label

label reader

The Result: Impending disaster.

Yeah, reading labels is boring stuff, but it's also essential, lest you exterminate your plants, pets, and yourself. Weed-killers won't kill bugs and bug-killers won't kill leaf spot, but both products could kill you if you don't use them properly.

So read the directions carefully. They'll tell you how much product to use, how and when to apply, what plants to use it on, and what pests it controls. And don't ever think if one tablespoon works great, two tablespoons work even better. The result is usually the opposite.

05 of 15

Spreading Weed & Feed With a Rotary Spreader

rotary spreader

The Result: Might end up feeding the weeds.

Granular weed & feed fertilizer kills the weeds and fertilizes the grass at the same time. The problem is that most people apply it using a rotary spreader, the kind that slings the granules across the lawn. This method is highly inaccurate and may cover sidewalks and driveways, where it does no good, or the foliage of good plants you don't want to kill.

People also apply at the wrong time. For weed & feed to work, the weeds must be actively growing in mild or warm weather, and the lawn must be wet. If the granules fall off in less than 24 hours or rain washes them off, all they do is make weeds grow faster. Instead, apply fertilizer and weed-killer separately, and use weed-killer from a ready-mix spray bottle that attaches to the end of a hose.

Listen to Grumpy Talk About Weed & Feed on Ask Grumpy

06 of 15

Pruning Flowering Trees And Shrubs At The Wrong Time

hydrangea

The Result: No blooms.

Some plants make flower buds on new growth. Others make buds on growth from the previous year. Pruning at the wrong time removes flower buds – hence, no blooms.

So here's a simple rule – prune trees and shrubs that bloom from winter through May (azalea, camellia, forsythia, quince, oakleaf hydrangea, spirea, redbud, flowering cherry) in late spring or early summer. This gives them time to make new flower buds for next year. Prune those that bloom after May (crepe myrtle, chaste tree, rose-of-Sharon, butterfly bush, peegee hydrangea, gardenia, pomegranate) in late winter or early spring. If you have any question about the right time to prune, remember this tip – the best time to prune any flowering tree or shrub is immediately after its flowers fade.

07 of 15

Scalping The Lawn

scalp lawn

The Result: A weedy lawn that needs lots of water and fertilizer.

Cutting grass down to the soil line does not mean you'll be able to mow less often. It sets the stage for a thin, weedy lawn that whines like a baby for food and water. Reducing the height of the grass by more than 1/3 in a single cutting stresses and weakens it. This provides the perfect opportunity for invading lawn weeds, such as dandelions, crabgrass, chickweed, Virginia buttonweed, and spurge, that don't mind being scalped. It also means you have to water and fertilize like crazy in between scalpings.

Solve this problem by cutting your lawn at the highest recommended height for your type of grass:

  • Cut Zoysia at 1 to 2 inches
  • St. Augustine at 2 to 4 inches
  • Centipede at 1 to 2 inches
  • Bermuda at 1/2 to 1-1/2inches
  • Kentucky bluegrass at 2 to 3 inches
  • Tall fescue at 2 to 3 inches

You'll mow less often and have a nicer lawn.

08 of 15

Mixing Together Too Many Colors

many colors of flowers

The Result: Your garden looks busy and loses impact.

You wouldn't go to work wearing yellow earrings, red lipstick, a blue dress, and green shoes (at least, Grumpy hopes you wouldn't). Then why plant your flower border that way? Resist the temptation to plant one flower of every color. Instead, maximize impact by planting sweeps of single colors.

09 of 15

Planting Shade Trees Between The Sidewalk And Curb

trees

The Result: Tree roots lift and break the sidewalk.

Growing roots have incredible power and can easily crack concrete. This is guaranteed to happen if the space between your sidewalk and curb in less than 6 feet and you plant shade trees that grow big and have roots near the surface. A few examples include Southern magnolia, oaks, maples, bald cypress, sycamore, sweet gum, and tulip poplar. Plant smaller, ornamental trees instead, such as crepe myrtle, redbud, dogwood, flowering cherry, crabapple, and orchid tree.

10 of 15

Not Identifying The Bug, Fungus, Or Weed Before Spraying

spraying weed

The Result: You make the problem worse.

Go into a home center today and you'll find long shelves crammed with dozens of chemical problem-solvers. Not one of them controls everything. By spraying for a pest without knowing what it is, you could kill off its natural enemies without killing the pest. Or you might use the wrong product and kill the plant. So if you can't identify a pest in your garden, take a sample to a nursery or your cooperative extension service and have them ID it for you.

11 of 15

Planting In Pots Without Drainage Holes

pots planting

The Result: The plant drowns.

Most plants need soil that contains plenty of oxygen. There is no oxygen in soil saturated with water. And that's what you get when you water a plant in a pot that doesn't have a drainage hole. It's like planting in a bathtub. So unless you're growing aquatic plants, always check to see that pots have adequate drainage.

12 of 15

Planting Trees And Shrubs In Teeny Holes

planting trees

The Result: They grow slowly or die.

Most tree and shrub roots grow within the top foot of soil. And they grow faster in soil that's loose and well-aerated than soil that's hard and compacted. So when you plant, make the whole at least 3 times wider than the root ball. But don't make it any deeper (see mistake #2).

13 of 15

Buying Plants With Bugs On Them

bugs on plants

The Result: You bring home bugs that spread to your other plants.

Know how most people get bugs on their houseplants, flowers, and shrubs? When they buy the plants, they buy the bugs too. Garden centers and greenhouses are perfect places for bugs to multiply, because plants are so close together. Plus, they're sprayed so often that pests become resistant. So thoroughly inspect any plant before you put it in your car. Pay special attention to flowers, flower buds, new foliage, and the undersides of leaves. Shake the plant to see if any bug flies off. If you find bugs, leave the plant there.

14 of 15

Buying The Biggest Shade Tree You Can Find

shade tree

The Result: You pay more, but you don't get more.

When a big tree is dug from a wholesale nursery, it leaves most of its roots at that nursery. So when you finally plant it at home, it spends the first 3 years or so replacing those roots, instead of growing new branches and leaves. A smaller tree grown in a pot, however, loses few roots and starts growing right away. In 2-3 years, it's the same size as the tree that's just sitting there. And it cost a lot less.

15 of 15

Mulching With Lava Rock

lava rock

The Result: Your yard looks like the slopes of Mount Kilauea.

Lava rock? Are you kidding me? What part of Hawaii do you think you live in? Listen, this is the South. We have tornadoes, we have hurricanes, but we don't have volcanoes. Covering your garden beds with red volcanic rock looks ugly and weird. Plus, instead of cooling the ground in summer, the way natural mulches do, it heats it up! If you want to convince your neighbors of your total lack of taste, this is perfectamundo.

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