Use of nematodes in greenhouses

Nematodes can be used in ornamental flower cultivation both in the open field and in the greenhouse. They can be applied using Dosatron fertiliser injectors, drip irrigation or overhead irrigation.

Protected cultivation – fungus gnats, thrips and butterfly caterpillars

The key pest for protected ornamental flower cultivation is the fungus gnat (Bradysia paupera), thrip (Frankliniella occidentalis) and butterfly caterpillar (e.g. Duponchelia fovealis, Opogona sacchari) nemastar® (Steinernema carpocapsae) controls caterpillars that eat the parts of the plant above ground. nemaplus® and nemaflor® are effective against thrips and fungus gnats.


Caterpillars eat the parts of the plant above ground and produce many generations each year. nemastar® should therefore be sprayed every 10-14 days, 4-5 times during the season. Apply 125,000-250,000 nematodes per m² or 1 million nematodes per litre of spray mixture. Ideally, spray the plants in the evening shortly before draining. The outside air temperature should be above 14°C during the day.


Thrips Frankliniella

Figure 1: Thrips Frankliniella

Spray 250,000 nematodes per m² using at least 100 ml water per m² until the water starts to drip. Apply in the evening to utilise the higher air humidity for the nematodes. Apply weekly as the nematodes only infest the larvae and pupa present at the time of application.

Fungus gnats

The nematodes must enter the soil. Apply a dosage of 10,000 nematodes per m³ soil or 500,000 nematodes per m². Usually, repeat treatement after 10 days. Preventative use of nematodes has proven effective, especially for young poinsettia plants.

Open field crops – vine weevil and crane fly larvae


Figure 2: Lifecycle Black Vine Weevil

The key pest for open field crops is the black vine weevil, Otiorhynchus sulcatus. It is vulnerable to nematop® or nematodes of the species Heterorhabditis bacteriophora. Besides vine weevil, crane fly larvae of the species Tipula paludosa and Tipula oleracea can cause problems in open field crops. They can be controlled effectively using nemastar® or nematodes of the species Steinernema carpocapsae.

nematop® is only effective against larvae and pupae, and can therefore be applied during April and May and from August to the start of October. The soil temperature should be above 12°C by day. nematop® cool can be used in March and October as it is effective from soil temperatures of 8° C and above.


Apply 10,000 nematodes per litre of soil for potted crops. With overhead watering, a higher dosage is required owing to loss depending on the pot disance. Likewise, the dosage must be increased if the soil contains compost.