Early Summer Greenhouse Pest Control Guide for Aphids, Whiteflies & Spider Mites

Summers are the best! But not so much for owners of an outdoor greenhouse because during this season, thanks to the rising temperatures, humidity and rapid growth in plants, it's the perfect condition in which pests tend to thrive. Without proper management, the greenhouse becomes the ideal place for spider mites, fungus gnats, aphids, and whiteflies to spread quickly. These pests damage the leaves, weaken the plants, and can quickly take over a backyard greenhouse.

This video is sourced from Youtube@Epic Gardening

To help you with greenhouse pest prevention, this informative guide covers the essential steps on how to identify some of the common pests, and the best pest control solutions for long-term prevention and  management.

Table of Contents

• Why Greenhouse Pests Increase in Early Summer
• How to Identify the Common Greenhouse Pests
• Safe & Organic Greenhouse Pest Control Methods
• Integrated Pest Management Greenhouse Guide
• Greenhouse Pest Prevention Strategies

Why Greenhouse Pests Increase in Early Summer

Pests are commonly found everywhere but the main question here is, why greenhouse pests increase in summer?  Understanding the root cause for this is the first and most important step towards effective pest control for greenhouses. Summer is great for many things, and it's also the time pests rapidly spread infecting the entire place. Even a small infestation can take over the entire enclosed greenhouse leaving you with damaged crops and plants’ whose health is slowly slipping away in a matter of a few days. Summer season creates the most favorable condition for pests to thrive in and here are some of the reasons why:

Warm Temperatures

When summer kicks in, the temperature starts to rise which leads to more hot and dry conditions and considering how within enclosed spaces, the temperatures are a lot higher in comparison to what's outside, and the fact that these spaces prevents heavy rain, wind or any natural disruptions from coming in,  pests take full advantage of this and start to rapidly multiply and spread more aggressively.

For example, aphids and whiteflies are known for rapidly reproducing during summers while spider mites often become a lot more active in dry conditions.

Poor and Insufficient Airflow

Without the proper flow of consistent and continuous airflow, greenhouse spaces become stuffy and congested with overcrowded overgrown plants who have no space to breathe and grow properly. Blocked vents and insufficient circulations cause poor air quality for these plants to survive on and leaves tend to remain damp a lot longer than usual. All these factors lead the way and pave the path of pests to settle and hold onto stressed out plants and weaken them over time.

Without proper air movement, the plants are basically being deprived of basic survival and the insects like whiteflies and spider mites make it their breeding grounds during the warm months.

Increase in Humidity

When it's dry, it's normal to keep watering to ensure the plants don't die. But all the increased watering and the unnecessary heat that has accumulated within the enclosed greenhouse causes increase in moisture and leads to greenhouse humidity pest problems. The high humidity level allows fungus gnats to increase and this makes the plants more prone to pest damage.

Humidity allows the pests and the insects to stay hidden under the leaves, around the soil surface and you can also find them glued onto the stem of the plant.They continue to reproduce and spread so quickly that it can't be detected immediately without paying close attention.

Rapid Plant Growth

In general, plant growth is a good sign for most places. But young plants tend to produce tender foliage that can easily attract insects who are in the feeding phase. For example, aphids are drawn towards soft new shoot growth because it contains a good amount of plant sap and some are in high concentration levels.

As these plants start to grow bigger and bigger during the initial days of summer, the dense foliage creates better hiding spots for pests to stay perched under the leaves and they can go unnoticed for a really long time. This makes greenhouse insect control a lot more difficult to curb, especially in a small greenhouse, where pests can spread quickly if plants are not checked and monitored regularly.

Now that we have covered the root causes for why pests increase during early summer time, let's take a look at how to identify some of the common greenhouse pests.

How to Identify the Common Greenhouse Pests

To prevent your plants from getting attacked and damaged, early identification of these pests is super critical for effective greenhouse pest management. The sooner you notice these little demons, the quicker you can mitigate their growth and the easier it will be to control the spread across the space. Let’s break down some of the most common pests, how to spot them and how they spread.

Aphids

These pests are basically small soft-bodied insects that are commonly found clustered together on stems, the underside section of the leaves, and when there is new shoot growth. Depending on its species, these little creatures can appear black, yellow, green or brown.

Here’s how to identify aphids in greenhouse:

• Curled up leaves or the ones that are distorted and not fully spread out.
• Residue of sticky honeydew that can be found on the plants.
• Weak and slow growth that you have noticed over a period of time.
• If there is honeydew, there will ants, this is another sign
• When the foliage starts to turn yellow from green.

They usually feed off by sucking on the sap from plants, and thanks to this, the plants’ overall health starts to weaken. It also causes severe infestations that  stunt the plant growth and spread various plant diseases especially in enclosed spaces like greenhouses.

To prevent these creatures from causing all the above damage, regular inspection especially around the new growth areas is super important because aphids tend to reproduce rapidly during warmer conditions.

Whiteflies

These are tiny white insects that are often found flying or hovering underneath the leaves. When they are disturbed, you can see them fill the air  in visible clouds.

Here are ways to notice whiteflies damage on greenhouse plants:

• Yellowing leaves
• Sticky residue on foliage
• Premature leaf drop
• Weak plant growth
• Sooty mold that develops on the honeydew deposits

These little creatures also thrive by continuously feeding off on plant sap and this becomes severe during early summers because they grow rapidly in warm temperatures, reducing photosynthesis and as a result, the crops start to weaken over time. 

Fungus Gnats

These are basically small dark insects that are commonly found flying near wet and moist soil surfaces. Adult gnats grow to become a big nuisance because they are difficult to get rid of but the larvae living and breeding in soil are also dangerous because they damage the roots of the plants.

Signs of Fungus Gnat Present:

• The tiny or small insects that are flying around the pots or trays
• When the seedling growth is not
• Despite good amount of watering, if you notice wilting
• Root damage in the young growing plants

When it comes to fungus gnats, it's usually linked to overwatering and excess moisture that's present in the soil. Fungus gnats in greenhouse soil make the surface wet and an ideal breeding ground for larvae.

Hence, paying close attention to the soil moisture levels is essential for effective pest control , especially against fungus gnats in greenhouses.

Spider Mites

Compared to the other insects, spider mites are extremely small and  you cannot easily locate them unless you inspect closely. They thrive under hot and dry conditions and are found on the underside of the leaves.

Signs of Spider Mite Present:

• Tiny yellow or white speckles  that can found on the leaves
• Fine webbing that happens between leaves and stems
• Dry and brittle foliage
• When leaves start to discolor and dropping rapidly

The spider mites symptoms on greenhouse leaves often start on a subtle note before  they become widespread. Because they reproduce quickly, even a small infestation can spread rapidly through the greenhouse.

Monitoring undersides of leaves regularly is one of the most important greenhouse pest prevention practices during early summer.

Safe & Organic Greenhouse Pest Control Methods

Many greenhouse owners look for eco-friendly and organic greenhouse pest control methods to control the pest situation because they are a lot more environment-safe and it eliminates greenhouse pests safely without harming or damaging the insects, the edible crops and the overall health and atmosphere of the greenhouse.

There are methods that provide effective greenhouse pest control solutions and mostly these are the ones that give you long-term results as well. Let’s dive deep into this and take a look at some of the effective measures.

Neem Oil Greenhouse Pest Treatment

Neem oil has so many benefits and it is widely used as an organic greenhouse pest control treatment for controlling the spread of aphids and spider mites. Neem Oil helps to disrupt the feeding and reproducing process and also curbs the insect development process. It targets several of the most common pests in one shot while simultaneously remaining compatible with other greenhouse pest management programs. 

When the oil is applied properly and carefully, it coats the leaf surfaces and targets the insects that's feeding on it.Since most of these pests tend to hind or are found underneath the leaves, the oil when applied everywhere especially in these hidden sections help to mitigate the problem and that's why it's one of the most sought after greenhouse pest control methods. Some of the best ways to use neem oil are:

• Always spray or test it on a small section before applying it everywhere.
• Spraying during the evening or early morning  because they are the cooler parts of the day and this helps to reduce the overall stress levels for the plants.
• Coating the oil on the underside of the leave thoroughly because this is a favorite spots for the pests
• Reapply the oil only if the product instructions recommends it

Neem oil is effective when it's utilized in the early stages. Bear in mind that if there is a severe pest outbreak, the neem oil might not be effective on its own and might require some combination with other products to mitigate the spread. Its often preferred by greenhouse owners who are seeking safer and longer greenhouse pest prevention strategies.

Insecticidal Soap for Greenhouse Insects

This is an effective option for controlling the spread of soft- bodied pests such as aphids and whiteflies. These soaps work wonders because they tend to break down the insect’s protective outer layers by causing severe dehydration and death upon close contact.

The insecticidal soap doesn’t leave any chemical residue behind so its very useful for smaller and more localized outbreaks.  It has a low level impact in comparison to other stronger pesticides while simultaneously helping owners manage the common greenhouse insect problems.

Here are some of the  benefits of the soap:

• Safer and more suitable for edible crops
• Has a very minimal impact on the environment
• Effective for controlling the spread of aphids and whiteflies
• Useful for targeted pest control applications

Since the soap only affects the insects that have direct contact with it, repeated usage is often necessary during the active infestation period and as an owner, it's important that you check and monitor the plants carefully because missed pests can quickly take over the space. Applying the oil consistently is great for long-term results and it also supports integrated pest management greenhouse practices.

Sticky Traps for Greenhouse Pests

These are a great pest control solution to reduce the population of flying insects such as whiteflies and fungus gnats and they are generally placed around the greenhouse to track the pest activity and detect early infestations.

Yellow sticky traps are the most commonly used ones because insects are attracted to bright colors and surfaces. Once the insects come in contact with the trap, they get stuck and can't escape. Now if you are looking at how to eliminate greenhouse pests safely, bear in mind that sticky traps cannot single-handedly achieve this, especially for large infestations.

Here are some of the advantages of stick traps:

• Helps with pest monitoring
• Helps with early infestation detection
• One of the non-toxic greenhouse insect control solutions
• Can be a useful practice to track the change in pest population
• Helps to identify the favorite spots for the pests within the greenhouse

Sticky traps can be handy when you want to track and monitor the seasonal growth or the increase in population during early summers. They also play a role in identifying if the other pest control solutions work effectively or not. For best results, check on the sticky traps, change or replace it once the surface is covered with insects, dirt or debris.

Biological Control

We covered different solutions and products to use as greenhouse pest control solutions and we have one left and this is rather a natural practice. Using living organisms  instead of always relying on chemical treatments makes a big difference to greenhouse aphids whiteflies spider mites control.

As a greenhouse owner, you can introduce natural predators or in other words biological and beneficial insects that target pests and can become a part of the integrated pest management greenhouse guide because it helps to reduce dependency on chemical products and boosts long-term pest management.

Some of these beneficial insects for greenhouse control include: 

• Ladybugs for controlling aphis
• Predatory mites to counter spider mites
• Parasitic wasps for targeting the whiteflies
• Beneficial nematodes for countering the fungus gnats present in the greenhouse soil

These insects should be a part of the bigger picture because it  combines early detection, monitoring, prevention, and targeted treatments throughout the pest growing season.

Integrated Pest Management Greenhouse Guide

Now that we have covered the different types of pests, how to identify and the different ways to mitigate their growth, here is a helpful list to carefully follow if you are looking for long-term greenhouse pest control.

Here are the key integrated pest management greenhouse practices you should try and do:

• Always monitor your  plants regularly for  common pests like aphids, whiteflies, spider mites, and fungus gnats. If they aren’t visible to the naked eye, remember the hidden spots to check.
• Placing sticky traps to attract and get the attention of flying insects.
• To prevent early infestation, remember to apply neem oil as greenhouse pest treatment.
• For treating infected plants, try and use insecticidal soap on the affected areas or sections.
• Try and use beneficial insects like ladybugs and predatory mites to target the existing pests.
• Improving greenhouse airflow pest prevention to reduce humidity buildup
• Avoid overcrowding by spacing plants to reduce pests greenhouse conditions.
• Always abide by the greenhouse sanitation pest control methods which observe basic practices like removing debris and infected plant material from time to time.

Sometimes these solutions can do wonders if they are used together or by combining one or two as they become a more effective and sustainable greenhouse pest management system.

Greenhouse Pest Prevention Strategies

Your measures to achieve effective greenhouse pest prevention starts with  having a routine in place and maintaining it by following healthy growing conditions during early summer. Here are some of the practices to follow:

Greenhouse Airflow Pest Prevention: Ensure that there is proper ventilation because this helps reduce humidity and stagnant air that encourage aphids, whiteflies, spider mites, and fungus gnats to thrive. Even in a heavy duty greenhouse, good airflow is essential for preventing pest outbreaks. Using roof fans and keeping  the vents open improves continuous greenhouse airflow pest prevention and supports better greenhouse insect control through the summer.

Spacing Plants to Reduce Pests Greenhouse: Make sure to leave some space between your plants because this improves the airflow and reduces unnecessary overcrowding in some areas where pests can hide and spread easily. Spacing also makes the process of monitoring plants easier while you are doing a routine check on them.

Greenhouse Sanitation Pest Control Methods: Make these things a habit, removing dead or fallen leaves, cleaning the tools from time to time, and disposing of the infected plant materials and sections All these simple yet effective steps helps to reduce pests from breeding and supports long-term greenhouse sanitation pest control methods.

Routine Monitoring: Checking on your plants regularly  helps to detect the early stages of pests  breeding  and this also helps prevent infestations from spreading quickly. Always keep an eye out for the leaves, the soil, and the sticky traps, because this is an important part of greenhouse pest control. 

Consistent and continuous greenhouse pest control management is very essential especially during early summer times when the pest activity increases rapidly. Catching these hidden problems early on can save and rescue your plants before it's too late.  Using the right combination of greenhouse pest management methods can make the early infestation period a lot more easier to control before serious plant damage happens. By focusing on prevention and using safe treatment methods, as an owner, you can maintain a healthier greenhouse and support steady and strong plant growth throughout the summer season.

More to read

Polycarbonate Greenhouse Vs. Plastic Greenhouse: Best Choice For Backyard Gardeners

Best Outdoor Greenhouses For Your Backyard: What To Look For Before You Buy