As a hobby gardener, you can use yellow sheets to protect your plants in the garden and indoors from various pests. We’ll show you how to use the sticky panels properly and how you can even make them yourself.
What are yellow boards and how do they work?
Yellow boards are one of the most popular ways to keep flying pests away from your plants in the garden, greenhouse or home. Yellow cards are made of thin cardboard or plastic coated with a non-drying adhesive. Pheromones or insecticides are not usually needed for glue traps, as insects are attracted solely to the color yellow and eventually stick to the adhesive layer.
At garden supply stores or online, you can get yellow boards either with an eyelet for hanging or as yellow stickers that you can stick directly into the potting soil. We’ll show you how to make them yourself, too.
Yellow boards for pest control
With yellow sheets you can protect your plants from aphids and fungus gnats, for example.
You can protect your plants from aphids and fungus gnats.
If your plants are infested with pests, you can control the spread of the insects with yellow panels. Especially flying pests can be controlled well with glue traps.
Depending on the insect species, glue traps with different attractants and colors are used. For example, yellow boards can be used to control the following pests in the home and garden:
- fungus gnats
- Cherry fruit flies
- Winged aphids
- Rhododendron cicadas
In the case of fungus gnats, yellow cards work well to effectively control the pests. However, in the case of other insects such as cherry fruit flies, the panels only catch a small portion of the animals. Therefore, you should always combine yellow boards with other natural pest control measures.
Important: If you want to use yellow sheets in your garden, you should use products with water-insoluble glue if possible. In the greenhouse or indoors, the classic yellow cards coated with glue are also suitable.
Are yellow panels a danger to beneficial insects?
A large number of insects adhere to the sticky glue of the yellow traps. Especially in the wild, this raises the question of whether the glue traps can also be dangerous to beneficial insects.
Fortunately, we can give the all-clear here: Bees, bumblebees and butterflies very rarely get caught on yellow boards. The flower pollinators concentrate more on the scent of nectar and flower colors when searching for food and are therefore not attracted to the yellow color. Another case, however, is the ichneumon wasp. This beneficial insect unfortunately lands more often in the glue trap because it wants to feed on the insects caught there. Various species of flies, such as the hoverfly, also frequently stick to the glue.
Conclusion: In an insect-friendly garden, yellow cards pose little danger to bees, bumblebees and co. If you still want to prevent beneficial insects from landing in the glue traps, you should first control pests with other methods.
How to use yellow traps correctly
After one or two weeks, replace the yellow traps with new ones.
After one to two weeks you should replace the yellow panels with new ones.
You can use yellow traps all year round to check your plants for pest infestation. It is best to use the glue traps as soon as the insects begin to fly. Many pests, for example, are already on the move by the end of March. In this way, you can see early on whether your plants are infested with pests and thus have the opportunity to quickly take further control measures.
This is how you apply yellow panels correctly:
- Take the yellow sheet out of its package.
- Depending on the type of product, you now attach the yellow card to one of the metal sticks provided or to the eyelet provided for hanging it up.
- Now insert the yellow card directly into the potting soil. Make sure that you do not place the trap more than 20 centimeters away from the endangered plant parts.
- You want to attach the glue trap to a tree? Then hang at least three to ten yellow boards well distributed on the branches, depending on the size of the tree crown.
- Check the yellow boards regularly for pests and then control them with further measures. You can also control fungus gnats with nematodes, for example.
- Replace the glue traps as soon as their adhesive effect wears off or they are too densely covered with insects. It is best to change the yellow boards every one to two weeks.
Make yellow boards yourself
Yellow boards are usually available for purchase, mainly made of plastic. If you want to save money and value sustainable pest control, you can also simply make the glue boards yourself.
For homemade yellow boards with sugar glue you need:
- yellow clay paper
- laminating foil and a laminator
- a hole punch
- a string for hanging or a toothpick
- kitchen thermometer
How it works:
- Cut out a rectangular card from the clay paper and laminate it with the laminator. This way you can use the yellow card in any weather and coat it with glue several times.
- Punch two holes in the bottom part of the card with the staple punch. If you want to hang the yellow card, thread a string through the holes. Alternatively, you can stick a toothpick in one of the holes.
- For the glue, dissolve about three parts sugar in two parts water in a pot. Then bring the mixture to a boil.
- Once the sugar solution boils, do not stir it, otherwise the sugar will crystallize and not stick later.
- Boil the mixture until it reaches a temperature of 105 to 115 degrees Celsius maximum. Check the temperature with a kitchen thermometer.
- Remove the pot with the mixture directly from the hob as soon as the necessary temperature is reached and place it in a bowl of cold water.
- Wait until the sugar glue has cooled down completely and do not stir it during this time.
- Finally, coat the yellow cards with the glue.
Especially practical: You can reuse these homemade yellow cards as often as you like. Simply scrape the trapped insects off the surface of the card and apply a new layer of glue.