| Maintype | Substrate |
| Crop | Cucumber |
| Croptype | Substrate |
| Variety | Roxanna RZ |
Roxanna RZ: for spring, summer and autumn cropping
Roxanna RZ is a cucumber variety suitable for spring, summer and autumn cropping. From trials conducted in 2006 and 2007 we now know that this variety may be sown from 20th January - end July. Promising trials using lights are currently in progress (January 2008).
Its crop type has a fertile character, with an open structure. The crop gives a slightly heavier impression than, for instance, Confida RZ, but is more open than, say, Sheila. What is also remarkable about Roxanna is that, depending on the growing system, it can give 1 - 2 leaves more below the wire than the other standard varieties. Growers find Roxanna an easy, workable variety that does not demand any complicated growing strategy.
The stem fruits are of a good length and the cucumbers on the laterals are not susceptible to being too long compared with the other standard varieties. Roxanna has a good shelf life and its colour is also excellent.
Roxanna does not have any mildew tolerance.
Tips for plant raisers
Roxanna does not need any special treatment during the plant-raising stage compared with the other standard varieties. In practice, depending on the desired plant type, there are no striking differences with other varieties, either. We do know, however, that this variety likes a sufficiently high feed level and that water uptake is often high. Roxanna may be sown from 20th January - end July.
Attention points when raising Roxanna RZ plants:
- Do not grow too generatively, i.e. keep temperatures level or use a 0.5°C decrease in the night temperature. This is more than enough to get Roxanna sufficiently generative.
- Should you have to supply older plants, space the plants out at the final distance at a very early stage (once the cotyledons are properly spread) e.g. 12 - 14 plants/m².
- If Roxanna is grown too generatively it will develop 2 - 3 fruits per axil, which is too much of a good thing.
- Roxanna is a cucumber variety without mildew tolerance, so carry out preventive mildew control at regular intervals.
Tips for growers
Start of the crop and stem fruit load
Roxanna has more than proved itself in the summer and autumn crops of 2007. It has shown that it can cope easily with any conditions such as different growing systems (high-wire and traditional cropping), a high stem fruit load, high summer temperatures and low light intensities in the autumn.
Up to the wire, depending on its height, Roxanna is capable of 1 - 2 leaves more. In crops started in April and May, an extra stem fruit load may be retained, in tandem with the extra leaves. We start retaining fruits at the 5th or 6th leaf. We subsequently allow single fruits up to about 4 leaves below the wire. We can then choose whether we allow 1 or 2 fruits per leaf, depending on a high harvesting frequency (every day) and optimum technical nursery equipment (light glasshouse, CO
2, watering and, possibly, roof sprinklers/humidifiers). Because of more vigour and leaves below the wire, the crop transpires more than other varieties. That is why controlling the watering too much is not advised. During sunny, bright April/May weather, water as normal during the day, with night watering rounds if necessary. Do not deprive the crop of water in the middle of the day!
Due to its great vigour, Roxanna may give a little more lateral growth on the lowest internodes during the phase without a fruit load. Remove it without delay, as it would waste the plant's energy.
In autumn crops, planted end July and in August, you have to ask yourself whether all stem cucumbers should be left. We prefer them to be thinned out somewhat, depending on the circumstances. Ensure that in these crops there is always enough vigour left for lateral development. This is certainly in Roxanna not an easily-occurring problem, but it does require some attention.
Especially in April plantings we have regularly been amazed by Roxanna's vigour when it comes to giving a lot of stem cucumbers. We have noticed, though, that the first picking comes no earlier than in, for instance, a Confida or Sheila crop, but because of its extra production capacity, this is more than compensated for at a later date. Naturally, the result also depends on a nursery's technical equipment and growing strategy. Sufficient water, CO
2 and aids such as a screen and/or roof sprinklers and humidifiers increase the possibilities.
Fertilisation and watering
Roxanna makes no special demands as far as watering is concerned, but we repeat: with its extra leaves below the wire and its higher production level this variety uses a lot of water. We therefore advise, depending on weather conditions, generous watering rounds and the necessary night watering rounds when the plant has a maximum fruit load.
As for feed, we like to see a high slab EC from the start: a good 3 mS/cm in the slab. Use an adequate start-up schedule with extra calcium (1 mmol) and preferably red EDDHA iron. From the moment the cucumbers start to swell, a potassium schedule should be used, preferably still dosing red EDDHA iron as well. Continue to add red iron until the main laterals are strong and well over the wire.
Second half of the crop
Once Roxanna has started to produce on the laterals, this variety does not require any further special steering or treatment. Keep up enough speed, certainly in an autumn crop, and remove leaves where necessary.
Crop advice given by the seller is not binding. Descriptions and recommendations in this manual are as accurately as possible based on experiences in trials and practice. We do not, however, under any circumstances accept any liability for deviating results of the product grown in accordance with such information. The buyer needs to satisfy himself that this manual is suitable for his local conditions and the crop he intends to grow.