How To Control Thrips On Roses In The Garden

Thrips are extremely small garden pests, but they can do a great deal of damage.

These tiny, slim insects belong to the group known as hemimetabolous which may feed upon plants and/or other insects, depending upon the species.

Thrips are a species who prey entirely upon plant matter.

Thrips damage on roses In the garden

They do this using their rasping/sucking mouthparts which look and work something like a soda straw.

Thrips have two jaw-like structures (mandibles).

The left mandible is strong and predominant and used to pierce plant tissues’ cell walls and extract nutrition.

The right mandible is considered vestigial.

In some species of thrips, an enzyme is injected into the plant tissues, making them easier to digest.

What Do Thrips Look Like?

Thrips are so small you will probably never see them or recognize them.

To the naked eye, thrips look like tiny brown, orange or yellow dots.

Under magnification, you will see they have very long, slim bodies.

They are yellowish-orange in color, and some types have fringy wings making them capable of flying a bit.

Thrips Life Cycle

Thrips reproduction is wildly successful because it is possible for female thrips to lay unfertilized eggs, which then develop into virtual clones of the parent.

Sexual reproduction is unnecessary and rare amongst thrips.

Thrips live a brief and hectic life.

The egg stage lasts for several weeks, but once hatched, thrips develop quickly.

There are two immature instars.

The first is an active stage, and the second is a dormant stage.

At full maturity, some thrips will develop wings.

What Can You Do About Thrips In The Rose Garden?

It is hard to know when you have thrips in your rose garden because they usually set up shop at the base of the rose petals, so they are very difficult to see.

If your rose blossoms are looking dry and withered, it’s an indication they may be suffering from thrips.

Browned areas on rose blossoms may be more obvious on light-colored flowers.

If thrips are feeding on your rose petals, you may notice a pattern of flecks on the leaves surrounding the buds and flowers.

In extreme cases, undeveloped buds may be deformed or may open only part way.

Bud drop may occur with a heavy thrips infestation.

When this happens, follow these steps:

  • Inspect your rose bush and find a healthy-looking flower.
  • Pick the flower and examine it closely, peeling back the outer layer of petals. Look at the base of the flower for tiny brownish-orange dots.
  • Below into the flower petals and look to see if this stirs movement of tiny orange/brown dots within.
  • Use a magnifying glass to determine whether or not these are thrips.

What Can You Do About Thrips?

It is very hard to get rid of thrips in your rose garden, so it’s better to prevent them.

Here are some preventative steps to take:

  • Keep your rose bushes well pruned, and deadhead spent blooms frequently.
  • Remove all damaged flowers and buds and foliage and dispose of them correctly in a sealed plastic bag or by burning.
  • Don’t allow grass and weeds to come in contact with the trunk or lower branches of your rose bushes.
  • Keep them trimmed back well.
  • Periodic spraying of insecticide can help prevent thrips infestation.
  • You may also wish to experiment with organic alternatives.
  • Parasitoid wasps and other natural predatory insects can help control thrips, but it is difficult for them to be effective because thrips typically live inside the folds of flower blossoms.
  • Most predators have a hard time coming in contact with them.
  • If you do use natural predators in your garden, take care not to use pesticides, which will negatively impact them.