On Nursery De Grevelingen, Endeavour RZ is grown for the first year. We spoke with Marc Groenewegen on 20 January.

General information

What made you choose Endeavour?
We have followed this variety for some time in the trials and were able to observe it as a trial on our nursery last year. The big advantage of this variety is its consistent quality throughout the season. The other main varieties in the segment always have certain periods during the year when the quality is not quite so high. Not so with Endeavour - it always looks beautiful. That's why we now grow this variety on the entire nursery.

How did the start of the season go?
The plants that were delivered met our expectations but were a little on the small side. That was a shame, because the combination of the dark weather and the cold made for a very slow start in those initial weeks. That created slightly pale crops which were difficult to get to flower. Right now the crop is looking fine again, especially on the 'early' nursery. The second truss is now almost fully flowering. We have noticed, though, that there are regularly 5 leaves between the first and second trusses. On the 'later' nursery the first truss is now flowering.

What are the set points at the moment?
Half an hour before sundown we have the pre-midnight of 14°C kick in and at 9.30 pm we gradually go to 17.5°C, which is maintained until 1.5 hours after sunup. In the afternoon we have a set point of 21°C. We are still opening and closing the screen mainlyby hand. The last two nights it closed again, but the five nights prior to that we did not use the screen at all. That is quite unique, really, for this time of the year. On the 'late' nursery we have plastic, but not on the 'early' nursery.

And what about watering?
In the 'late' glasshouse we have practically not watered at all yet - the substrate has dried out there by 20%. In the 'early' glasshouse we did water during the last fortnight: twice a day, with an extra round when there was a lot of light. Many fellow-growers would be quicker to opt for a night watering round, but I prefer to water the plant at the time it needs it. We don't want to let the substrate dry out any further, either; we don't mind if the moisture percentage rises a little on light days. We water with an EC of 3.5. It was 4.5 for a while but the EC value in the slab is 8.0 at the moment, so we don't need to have the EC in the water quite so high anymore.

Is there anything in particular you would like to mention?
At the moment we are retaining an extra stem in both glasshouses, which will take the final stem distance to 35 cm. We did notice that the quality of the first sideshoot is on the moderate side: the leaf below the truss is relatively low. We are also hoping for some more light and for the time being we are not steering Endeavour any differently than we were used to with the other varieties.