Bugs this week 2023-12

These pictures you get if a grower gets enthusiast about predators, system thinking.

Predated aphids on clover below the table-tops
Natural hover fly early in the spring
Natural Feltiella early in the spring

And to be honest, it is unbelievable how predators populations develop. So early in the season (March in Norther Germany is still Cold): Aphidius, Feltiella, Hoverfly, next to lots of other insects. Beautiful to see.

Strawberry heating: Radiation – Temperature

The relation of temperature with radiation is very important in plant development. It is one of the first subjects in plant architecture.
– If temperatures are low related to radiation, plants grow compact: more vegetative
– Relative high temperatures give long stretched plants: more generative

Below a table with the optimum relation between radiation (both radsum as well as Watthours) in the languages Dutch – Hungarian – English.

The temperatures shown here are the 24 hour averages. It would be nice if we could use these for the current day. With some corrections during the day that might be possible, but it is not necessary for the current day. Goal is that the 3 day average temperature and radiation agree, so not necessary for every single day.

Example today we have 1150 Joule, goal for 24 hour temperature is for standard growth 16,1 oC. If you want an eary crop, and you the LAI is good enough you can also raise your temperatures and use the “fast growing” column, thus with 1150 Joule go for 18oC temperature.

Calculation of radiation from your LEDS:
capacity of LED in umol/m2/sec x 0,0036 = PAR mol/m2/hour
Example: capacity LED 200 umol/m2/s –> 200 x 0,0036 = 0,72 mol/m2/hour PAR
10 hours light from LED = 7,2 mol/m2/day PAR

Christmas 2022 new year 2023

A time to think back and look forward.
Thinking back, you may see the pictures in this post. All a beauty in itselve i think. For me every picture shows the huge complexity around strawberry. A very small part of creation, where from strawberries not even 1% is discovered or known of what is good to know.
I see:
– growers working as good as they can to grow beautifull and dilicious strawberries
– propagators, using all their time and energy to have excellent plants
– breeders investing all their knowledge for better varieties
How many man-years would it take a breeder to breed a new variety: 10 man-years?
And what about whole new strawberry plants? How many man-years would it take to breed or produce 1 strawberry plant out of nothing. In all its complexity: evaporation, stomata, roots, energy production, hormons, photosynthesis, pollination, plant reaction to: humidity, temperature, insects, fungi etc.

Looking forward, take your time to enjoy the crop you are working with. In all its beauty, complexity, excellent taste etc.
For me to see all this complexity and the work we do to keep them as good and beautiful as possible, also means, it didn’t pop up just out of the nothing. A great Infinite Designer made them for our joy.
Christmas means for me: after this year, a new one is waiting. After this life, a new one is waiting, because Christ made it possible.

Wish: blessings in Christmas, blessings for the new year and joy in your life.

Info this week 36

The end of season is approaching, so predators are more seldom. Therefore some other pictures that might be interesting.

The one i love the most is the young lacewing larva, eating its way through a colony of spider mites. They were really doing a good job there.

The effect of an wetting agent is also good to sea.

And the the differences in the air in the substrate. In this case the coir with lots of air and the peat with only a little air.

The leaf wasp is a very active insect. The larva can cause lots of damage and are very hard to control. They look like a caterpillar, but don’t react on the same treatments unfortunately.


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Bugs this week (30)

Yes, not only bugs. But a little more. I also smuggled a little mildew statistics in, and a little weed-climate issue.

Mildew statistics: Important to know about the scaling: 0 = no mildew; 3 just not acceptable; 5 = full with mildew. Two things are quite interesting i think:
– The total level of mildew is very acceptable, although growers hardly spray
– The everbearers don’t have mildew (or on a really low level). Although these growers dont spray.

Weeds below the table tops.
No, it doesn’t look that clean, but it has quite some advantages:
– Much better / stable climate. Especially in last weeks hot climate.
– Much more predators.

Flowers. Several flowers are attractive for Trips and or Orius. The differences between the flowers are quite huge. My son is doing a research right now after the differences between some of them. Good to see.


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Feltiella feeling good

Bugs this week 26 / graphs

This week some more pictures and some graphs of the current situation in the Norther part of the Netherlands.

Among the pictures you see one picture with black flower buds: Overpressure due to a combination of very active roots (good condition, high temperatures + no evaporation (high humidity). In this case pressure causses tissue damages on the weak tissue in the plants (generally: flower buds, young leafs and very young runners).

Below the development of the aphid population this year. The level is the following: 0 = nothing 1 = every now and then an aphid 3 = limit of acceptable 5 = totally full with aphids

Milldew development can be seen in the graphs below. It is very clearly, that the coincidence of milldew is increasing. Althoug the highest level is still on 2 (acceptable), but action is needed.

Those graphs is one of the things i like in my scouting app (FarmQA).

Below this weeks bugs.


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Bugs this week 22-25

Some interesting bugs at work in strawberries. Especially from the hoverfly and aphidoletes i have seen amazing activities.

Important in all this is that you have the good climate / settings: direct around the crop (grass, clover, flowers) and not far away some flower zones with flowers attracting predators.

Egg hoverfly

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Covercrops – Flower borders

Fruit Growers Tasmania is an organisation for the support of their member growers in the total range of growing and marketing fruit. I admire the way they assist their growers in almost everything a grower might face (contacts with government about corona, labor; export regulation; growth technical information etc). Fruit Growers Tasmania yearly organizes conferences about the crops they support. This year i could do a presentation about covercrops and flower borders in strawberries.

Withgoing the presentation and pictures used for a presentation about covercrops below table tops / gutters outside, in rain coats (open tunnes) and greenhouses and flower borders in order to attract predators close to strawberries.

Link to the presentation: covercrops flower borders

Aphids + predated on grass below table top

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Grass – Straw – Berries

Grass / Clover or another cover crop can be a huge camechanger. I see more and more growers changing from an artificial soil cover to a cover crop. Main reasons are:
– much better climate:
– in hot summers it can be till 6 oC cooler with an active cover crop
– higher humidity or better a humidity buffer – causing less problems with mildew

  • Much better climate:
    • In hot summers it can be till 6oC cooler with an active cover crop
    • Higher humidity or better: a humidity buffer with smaller differences between higher and lower humidities. Causing significant less problems with mildew
  • Hiding place / buffer for predators. I normally see more and more predators like:
    • predatory mites
    • aphidius and aphidoletes – sometimes together with some aphids
    • hover flies
    • and sometimes lacewings


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