Results 2025

Results MoestuinMix 2025

One of the aims of our experiment was to harness knowledge from allotment/vegetable gardeners that could be of value to arable farming, especially when it comes to strip cropping or other forms of crop-diverse cropping systems. We asked participants all to choose a crop of choice to combine with broad beans and also why you chose this crop.

Below you can read our preliminary results of 2025. To improve our conclusions, we will repeat the experiment in 2026.

Top 10 choice crops

Below you can see the top 10 of combination crops chosen by participants in 2025. After that, you can read the most common reasons for combining this crop with broad beans.

1. Carrot – Kan tegelijkertijd (vroeg) gezaaid worden met de tuinbonen; tuinboon geeft stikstof en schaduw aan wortel; wortel is een knolgewas, net als rode bieten; de oogst valt iets later dan oogst tuinbonen, waardoor je langer kunt oogsten van hetzelfde stukje grond.
2. Various types of cabbage (zoals bloemkool, broccoli, sluitkolen, paksoi, koolrabi, etc.) – Wortel/knolgewassen passen bij rode biet; kolen profiteren van de stikstof van de tuinbonen; kolen zijn nog vrij klein zolang de tuinbonen groeien en als de tuinbonen geoogst zijn is er voldoende ruimte voor grote kolen.
3. Pods, peas and capuchin peas – Worden net als tuinbonen relatief vroeg in het seizoen geoogst, zodat er daarna ruimte is voor andere gewassen zoals uitdijende pompoen; handig in de wisselteelt want allemaal zelfde plantenfamilie (vlinderbloemigen); vergelijkbare bemestingsbehoefte als tuinboon; kunnen beide tegelijkertijd beschermd worden tegen vogelvraat; hogere cultivars houden tuinbonen uit de wind.
4. Onions – Gelijktijdig groeiseizoen met tuinbonen; verjagen mogelijk slakken, luizen en andere plagen; als test om te zien of uien ook natuurlijke vijanden van plagen verjagen.
5. Potato – Kan de stikstof van de tuinbonen goed benutten; heeft een gelijktijdig groeiseizoen / vergelijkbare oogsttijd als tuinboon; luizen in de tuinbonen trekken natuurlijke vijanden aan die mogelijk ook gunstig zijn voor plagen in aardappelen; ruimtebesparing.
6. Lettuce – Same growing season as broad beans.
7. Spinach – Same growing season as broad beans; results from the 2024 season indicated a possible positive effect, so one participant wanted to test it again.
8. Chard – Lijkt op rode bieten; profiteert van stikstof van tuinbonen; makkelijk te telen.
9. Flowers (lots of nasturtiums and marigolds) – Cover crop/attractant for pests (mainly aphids); attracts pollinators; looks attractive.
10. Herbs, voornamelijk dille – Verjagen van  plagen/luizen; even hoog als tuinbonen.

In addition to these specific reasons, for almost every crop chosen, respondents also mentioned that the crop was chosen because it fitted in with the crop rotation schedule or vegetable garden planning, or that it was simply an experiment without any specific reason.

Yield

Which crops are good neighbours for broad beans? To find out, the participants all tested two combinations: broad beans with red beet and broad beans with a crop of their choice. They then reported the yield of the broad beans to us.

Difference scores

For each garden, we calculated the difference between the yield of beans next to red beet and the yield of beans next to the chosen crop. The difference between these two is the “difference score”. You can see these scores for each chosen crop in the graph below. The green bars show neighbouring crops that had beans performing better than next to red beet, and the red bars show crops where the beans performed worse than next to red beet.

All selected crops for which we have received harvest data are included in the graph. This means that some scores are based on only one or a few gardens. The frequency with which the crop occurred is indicated for each crop by the small numbers below the bars in the graph. In general, the lower the number, the more uncertain the result, because there were too few gardens with that crop.

Statistical analysis

When the selected crop occurred at least five times, we performed a statistical analysis to see what effects we could prove. This test shows that there are nine crops alongside which the beans produce a significantly better or worse (number of pods) than the beans alongside the red beets. The nine significant differences found are marked with an * in the graph.

Footnote: 1) Significant could be interpreted as “meaningful”, but in statistics it means that we are 95% certain that an effect exists and that it is therefore not a coincidence.

Good and bad neighbours

Leek appears to be a significantly better neighbour for broad beans than red beet– resulting in higher bean yields – while legumes, carrots, potatoes, garlic, courgettes, beans, herbs and flowers are significantly worse neighbours for broad beans compared to red beet.

It is striking that there are more neighbouring crops that result in a poorer yield of broad beans than crops that result in a better yield of broad beans, compared to red beet. Leeks are the only crop that scored significantly positive this year, while legumes (sugar snap peas, garden peas, capuchin peas), carrots, potatoes, courgettes, beans (running beans, string beans), herbs and flowers scored worse than red beet as companion crops for broad beans. It is apparently difficult to beat the combination of beetroot and broad beans.

Comparison with 2024

It is also striking that last year's good neighbours (celery, spinach and legumes) are not scoring as well this year or, in the case of legumes, are even significantly worse than the broad bean-red beet combination. Relatively poorer neighbours from last year (flowers, beans, onions, carrots and maize) are again not performing well this year. Whereas courgette was the best neighbouring crop last year (albeit not significantly), this year it is significantly worse than red beet.

The results also show that sufficient data is important in order to draw reliable conclusions. It should be noted that last year, all combinations were compared with broad bean-pumpkin, not with broad bean-red beet.

Would you like to read more on the results from the first year? Read the results of 2024 here.

Pollinators, aphids, and natural enemies

Results concerning pollinators, aphids, and natural enemies are still being analysed and will follow later.