In June 2018, Biobest Nederland performed an online survey of 141 Nutrimite users from the Netherlands. Biobest introduced Nutrimite, a food supplement based on Typha pollen, onto the market in 2013. The product stimulates the population development and improves the distribution of predatory mites throughout the crop.
One third of users in the Netherlands participated in this study. The majority of those questioned use Nutrimite for supplementary feeding of A. swirskii, followed by A. montdorensis and, in third place, A. degenerans. In the Netherlands, Nutrimite is used primarily in sweet peppers, potted plants, cucumbers and cut flower crops (see graph).
Eighty-two percent (82%) of the Nutrimite users were satisfied with its effects. The majority of Nutrimite users indicated that the predatory mite population in their crops increased by 25% or more as a result.
When we focus in on the crops in which Nutrimite is most commonly used in the Netherlands, such as sweet pepper, we see that 90% of current users were satisfied with the results. Here Nutrimite is mainly applied in the first two to six weeks of cultivation and respondents indicated that the introduction of the predatory mites (mainly A. swirskii and A. degenerans) as well as the spraying of Nutrimite were considered to be relatively easy to very easy.
In potted plant cultivation, 66% of those taking part in the survey supplemented their predatory mites with Nutrimite. In the majority of these cases, the predatory mites (mainly A. swirskii and A. montdorensis) were given the supplement every 14 days. The potted plant growers rated distributing Nutrimite as relatively easy to very easy.
Of the eight cucumber growers who completed the survey, six were supplementing with Nutrimite at the time of the survey. The other two had already stopped, since their growing season had ended. All users questioned were very satisfied with Nutrimite and had seen their swirskii populations increase by 25%. The approach varied from grower to grower with some supplementing only during the first two to six weeks; others supplemented every 7 or 14 days.
The spraying of Nutrimite and the distribution of the predatory mites was rated as being relatively easy to very easy.
The majority of cut flower growers surveyed gave supplemental feeding to the predatory mite population. In most cases, the predatory mites (mainly A. swirskii and A. montdorensis) were given the supplement every 14 days. However, several growers only supplemented immediately after introducing the predatory mites. Growers saw between 15% and 75% growth in the predatory mite population when they used Nutrimite and, generally speaking, were very satisfied with this performance. The most noteworthy reason that growers stopped using Nutrimite was that the predatory mites had sufficient prey available to them in the summer season. As a result, the need for supplementation was significantly reduced.
Rose growers indicated that while it was difficult for them to express in numbers the impact of Nutrimite on the E. gallicus population, they were generally speaking satisfied with the product.
Vegetable seed production
Finally, one survey respondent conveyed a positive experience using Nutrimite in the seed production of open-field vegetables. This grower, who applied Nutrimite on a weekly basis, saw his swirskii population increase by an average of 20% and was extremely satisfied with the result.