Do you see yellow dots on the leaves of your plants, or perhaps dull spots? Then look closely at the underside of the leaves. Very likely you will see tiny spider mites crawling there. These are only 0.5 mm in size and usually beige in colour, with two dark spots on the sides of the body. If you find spider mites, you should definitely take action, because in time the leaves will yellow completely, webs will form between the leaves and the plant will die.
The most common spider mite is the two-spotted spider mite, Tetranychus urticae. There are several species of predatory mites that feed on twp-spotted spider mites. Phyto-mite contains the species most commonly used, Phytoseiulus persimilus. This species feeds exclusively upon two-spotted spider mites.
Phyto-mite: predatory mites for spider mites
The predatory mites in Phyto-mite are about the same size as a two-spotted spider mite. Phyto-mites are red, and they crawl much faster than spider mites do.
Phyto-mite is the best predatory mite to contain a larger spider mite infestation because it exclusively eats spider mites. To give you an idea: every day, an adult Phyto-mite eats about 20 eggs or about 5 adult spider mites. The predatory mites actively search for their prey and suck them dry. You can see this by observing the empty exoskeletons of the spider mites left on the underside of the leaves.
When to use Phyto-mite predatory mites?
- Use Phyto-mite at the onset of spider mite infestation, not preventively.
- For use indoors or in greenhouses.
- Eats two-spotted spider mites on houseplants.
- Eats two-spotted spider mites on vegetables such as aubergines, cucumbers, capsicums, beans and melons.
- Phyto-mite does not do well on tomato plants! Use Forni-mite instead.
- Eats two-spotted spider mites on strawberries, grapes and fruit trees in greenhouses: such as mandarins, peaches, apricots and kiwis.
- The ideal temperature for Phyto-mite is between 22°C and 28°C. The mites don't do well at temperatures above 30°C, and stop working entirely at 35°C. For high temperatures, use Forni-mite instead.
- The night temperature must be a minimum of 6°C.
- The higher the humidity, the better it is for Phyto-mite. If you don't have a humidifier, mist the plants regularly with a plant mister. In a greenhouse, you can wet the ground every morning to keep the humidity high.
How to use Phyto-mite predatory mites
Phyto-mite is delivered in a tube filled with substrate. The mites are dispersed throughout the substrate. They should be applied to the plants as follows:
- Tap small piles of the contents of the tube directly onto the leaves of the plants.
- You should concentrate the mites as closely as possible to the center of the infestation, and also up to two meters around the infestation.
- If it's not possible to release the mites directly onto the leaves, use Bio-Boxes or coffee filters that you hang in the plants.
- If using coffee filters, you should cut them short so that the mites have less distance to travel to get to the infestation.
- If using Bio-Boxes or coffee filters, hang them in the plants first in as many introduction points as possible. Then shake, tap, or spoon the Phyto-mite (a few tablespoons per introduction point) into the Bio-Boxes / filters.
- Repeat the treatment after two weeks if necessary.
Combining Phyto-mite with other predatory mites?
Phyto-mite can be combined with Forni-mite. We offer a combination package with these two mite species.
Phyto-mite feeds exclusively on two-spotted spider mites, which is useful for heavy spider mite infestations. In addition to eating two-spotted spider mites, Forni-mite feeds on many different species; including other types of spider mites, thrips, and pollen. For this reason, Forni-mite can survive longer in plants than Phyto-mite.
Forni-mite is less sensitive to warm and dry conditions than Phyto-mite. They are more tolerant of temperature swings and low humidity.
How many predatory mites do I need?
This depends on the level of infestation. You should make sure that your army of beneficial mites is larger than that of the spider mites. We recommend releasing between 50 and 250 predatory mites per square meter. The faster you intervene, the fewer mites you will need to release in order to get the infestation under control.
Spider mites on houseplants
If you only have a few affected houseplants, then a dose of 500 predatory mites is usually sufficient. If you have large plants and they are heavily infested, then you will need to release 2000 or more predatory mites per treatment.
Spider mites on vegetables
The following gives an indication of how many mites to release, based on crops that are a maximum of 60cm high. Here we are thinking of crops such as capsicums, aubergines, strawberries, etc. For crops of 180cm, such as cucumbers and melons, you will need to multiply the dosage information to calculate the proper amount of mites to release.
- Light infestation showing little leaf damage and no webs: 30-50 predatory mites per m².
- Moderate infestation showing several leaves with yellow spots or patches: 50-100 predatory mites per m².
- Heavy infestation with many yellowing leaves and visible webs: First prune the plant to cut out the most heavily affected leaves. This will physically remove a large number of mites. Then release 250 predatory mites per m².
Spider mites in fruit trees or grapes?
The dosage guidelines for grapes are similar to those described above. You need to calculate the number of m² of leaf area and multiply this by the number of predatory mites in proportion to the infestation.
Likewise in fruit trees such as peaches, kiwi, etc., you need to estimate the number of m² of leaf area and multiply it by the number of predatory mites in proportion to the infestation.
Tip: You should see a significant improvement after two weeks. In case you do not see an improvement, you will need to treat again.
Will the predatory mites reproduce?
Humidity plays a major role in the reproduction of predatory mites. In fact, Phytoseiulus eggs require a humidity of 80% to hatch. At lower humidity levels, the eggs dry out and therefore do not reproduce.
You should not count on the predatory mites being able to reproduce in your plants. This is why we recommend releasing the quantity needed to solve the spider mite infestation with the purchased generation.
Can I store predatory mites?
Predatory mites are living beings that are delivered in a substrate. It is best to release the mites the same day that you receive them. You can store the mites in the package for a couple of days if necessary, but it is best to release them as soon as possible. We ship fresh products daily to guarantee you the best possible quality.
Should you need to store Phyto-mite for 1 or 2 days, it is best to do this in the refrigerator at a temperature between 6-8°C. Keep in mind that most refrigerators are kept colder than this. The best place to store the mites in the refrigerator is therefore in the door of the refrigerator where temperatures are a little higher. Always store the tubes horizontally so that the mites remain optimally distributed in the tube.
Combining plant sprays with predatory mites
You should not combine chemical or natural sprays against spider mites with predatory mites. In case you have already sprayed your plants, please contact us so that we can advise you how long to wait before releasing predatory mites. The waiting time strongly depends upon the active ingredients of the spray.
Questions?
We have more than 30 years of experience in the biological control sector. You can always contact us with your questions. We will be very happy to help you by offering personalized advice.
