Week 35-38: August 28 - Sept. 24
Project 1 - Giant Onions
I have not watered the onions with CANNA Coco A & B for 5 weeks now but I did give a light watering of CANNA PK 13/14 in early September, as I was still concerned about the soft bulbs. The onions have lost more leaves, although the Coco grown plants have retained more green foliage than those grown in soil. The CANNA Coco grown bulbs are certainly a lot taller, with stronger necks than those grown in soil. I did not lift any bulbs until a few days before they were needed for the Malvern Show on September the 22nd. I had to strip a few soft outer skins off when I did lift them, but the bulbs were sound underneath and dried out nicely in time for showing. The roots were clean and white. I found that the Coco was very wet underneath the bulbs, even though they had received no water at all for the last 3 weeks of growth.
However, I had a clear winner in the Single Heaviest Onion category with a CANNA Coco grown onion, which weighed in at 7.38kg after the leaves were removed. I also received second place in the Heaviest Three Onions category with CANNA Coco grown onions tipping the scales at 17.20kg. The winner just pipped me with a weight of 17.40kg. I am reasonably happy with this result, however having to remove the soft skins from the onions cost me a win in the Heaviest Three Onions Category.
CANNA Coco grown bulbs lifted for the Malvern Show.
CANNA Coco grown onions with healthy white roots.
High CANNA Coco grown winning bulbs on left at the Malvern Show.
50 L CANNA Coco rootball showing a good onion root system.
Project 2 - Giant Cucumbers
Heavy Cucumbers
This month I continued to water the cucumbers in the same way that I had done in August, until cutting the fruit for the Malvern Show. The weather remained poor during this period with rain, cool nights and little sunshine. Mildew spread to most leaves despite spraying with CANNACURE. It is possible that if I had used CANNACURE much earlier, I could have prevented the mildew taking hold. Next year I will be more proactive in my use of CANNACURE. The growth of the cucumbers stopped early in the month. I cut the largest fruit estimated by length and circumference measurements and exhibited it at the Malvern Show. Unfortunately, I only achieved 5th place in what was a strong class this year. The cucumber weighed 9.20Kg, which was well below the 11.98 kg fruit that I grew last year in CANNA Coco. All of the remaining plants are carrying a good healthy fruit, but two of the cucumbers have turned yellow/orange and are ripening.
Mat of healthy roots from the CANNA Coco grown cucumber show at Malvern.
Heavy Cucumber cut for the Malvern Show
Project 3 - Leeks and Tomatoes (Experimental work on the side)
Although it's not something I have included in my monthly diaries, I have also been working on some ideas for next years season. I grew three Long Leeks in recycled CANNA Coco, watered/fed in the same way as per the CANNA grown onions and they appeared to like the water holding capacity of this substrate. I have included a photograph of the leek root system from a 50-litre pot. In 2018 I plan to grow both exhibition and heavyweight Leek in larger (130-litre) pots.
Leek and its root system grown in recycled CANNA Coco in a 50-litre pot
I also tried growing a giant radish in recycled CANNA Coco this summer in my shed. I sowed the seed directly into a very large deep tray (but not deep enough) and once germinated, I ran a light over it for 13hrs each day (long days induce radish to run to seed) and watered/fed it as per the onions and leek. The radish grew without any problems. I stopped watering it 3 weeks before the show whereupon the Coco had almost dried out making easy to remove. The result was a new UK record at 10.38kg (see the attached photograph).
A new UK record raddish grown in recycled CANNA Coco
Week 31-34: July 31 - August 27
Project 1 - Giant Onions
The August weather has been cool, cloudy and wet with some short bursts of hot sunshine. These conditions seem to have allowed the onions to recover from the heat waves that we have experienced during the previous two months, and they are continuing to increase in size. The plants have lost many green leaves over the month and no new ones have replaced them. All but one of the CANNA COCO grown plants have retained more green leaves than those growing in soil under otherwise similar conditions. Last month I removed the black and white polythene from all Coco grown onions and simultaneously reduced the volume of water/feed that they received. Despite this, and despite the fact that I stopped watering the Coco grown plants completely two weeks ago, the substrate remains wet and I am still finding soft spongy skins under the best plants. I have had to remove more outer layers from the bulbs in an attempt to keep them sound. I have also set up a small fan to blow around the base of the best Coco grown plant in an attempt to dry it out a little.
Photo 1: Greenhouse onion
Photo 2: Best onion?
Photo 3: moveable pot
Photo 4: on left, onion in 50 litre pot
I watered with CANNA Coco A & B, CANNAZYM and RHIZOTONIC (EC 1.4, pH 5.9) and also with PK 13/14 early in the month. However I used only half the quantity per plant compared to last month. I will not water/feed again this season. The idea behind boosting phosphorus and nitrogen levels in the feed by using PK 13/14, was to see whether it would firm up the onion bulbs. It is not clear that this approach has been successful. I am concerned that the Coco grown bulbs remain softer than those grown in soil and I think that they are unlikely to be as heavy at harvest, although no Coco grown bulbs have so far been lifted. Most heavy onion shows are in September and I am hoping to show a Coco grown onion in the ‘As Grown‘ Class where their fresher green tops may prove an advantage.
Project 2: Giant Cucumbers
Cucumber growth has slowed during August, perhaps due to less sunshine and cooler nights. When I wrote my July diary entry the cucumbers were more advanced than they were at the same time last year, but after exposure to cooler, darker conditions this month, they have finished August behind last year's best.
I am watering every two or three days at EC 1.9, pH 5.8 and up to 8 litres per plant. At the last two feeds, I have added CANNABOOST Accelerator at 2 ml per litre. I have not yet increased the supports for each cucumber as I do not want to restrict growth in the length of the fruit. However, I will need to provide sling supports underneath them soon. All cucumbers have now turned from green to pale yellow and one is now completely yellow. I think this means that they are ripening and that growth will now slow down. The last two nights have been much cooler with temperatures decreasing to 5°C in the garden and being only marginally higher in the growing tunnel.
I am enjoying growing onions and cucumbers in CANNA Coco and would like to grow leeks next year for the Heaviest and the Exhibition Classes. I have grown three leeks this year in recycled Coco and they appear to like its water holding capacity, perhaps more so than onions. Having said this, we must await the final result later this month at Malvern.
Week 27-30: July 3 - July 30
Project 1 - Giant Onions
The first two weeks of July have been hot and dry. To keep the temperature down around the onion bulbs, I’ve been running air coolers in both the greenhouse and the tunnel, and have also shaded these areas from the hot sun. All bulbs have lost more, older dry skins, most of which have peeled down to the compost surface, but remain attached. The numbers of green leaves are reducing as no new ones are now forming. In the last 2 weeks of July weather conditions became cool, dark and wet, so I removed the shading and closed both the greenhouse and the tunnel most nights. The movable outside onions were also brought inside at night. I’m not seeing any benefit to moving these onions outside to take advantage of the fine weather, and back in to protect from inclement conditions. I’m concerned that the substrate in the Coco grown onions has been too wet around the bulbs, as I have found soft rot in the outer skins around the base of the Coco grown onion in the greenhouse. For this reason, I have removed the black and white polythene from all Coco grown onions and will water around the container edge only.
I’m watering with CANNA Coco A & B, CANNAZYM and RHIZOTONIC (EC 1.4, pH 5.8) but less frequently than I did in weeks 23-26. At the last feed, I also started adding CANNA PK 13/14 to boost phosphorous and potassium in the feed, to firm up and ripen the bulbs, as they seem a little soft for the moment. Overall the onions have grown little this month and have almost stopped increasing their girth. Some extra height is still being added and most of the CANNA Coco grown plants are retaining more green leaves than the soil grown onions, although the soil grown onions appear generally larger, there is overlap in their sizes such that the largest of the CANNA Coco grown plants are larger than the smaller soil grown bulbs. At the current time, the largest of the Coco grown onions has a girth of 710mm, whereas the largest of the soil grown onions has a girth of 740mm.
Project 1 - Giant Cucumbers
As alluded to in the onion diaries, early July was very hot and dry. I’ve shaded the cucumber plants with fleece during the hot, sunny days while they were growing quickly to avoid scorching of the young growing tips. During this warm period, I needed to water with CANNA Coco A & B, CANNAZYM and RHIZOTONIC (EC 1.5, pH 5.8) every 2 or 3 days. In mid-July, the first female flowers set on most plants. In the 2nd half of July, plant growth slowed as the weather cooled, but the young cucumbers have really grown quickly in the last 2 weeks, with the largest already measuring 0.5m long.
At the end of July, I top dressed the surface roots of each 100 litre CANNA Coco growing container with 25 litres of Coco and replaced the Black & White polythene. Additionally, I supported the young cucumbers securely, as they were placing a strain on the vines. I have taken out the growing tips of the main stems on half of the plants now to stop them growing. This should force them to concentrate their energy on fruit production. Watering frequency was reduced to twice a week during this cool, dark, wet period.
I have also sprayed the older, lower leaves with CANNACURE as a preventative measure against powdery mildew. I will continue treating the leaves throughout August but will treat the whole of the plants. One of the six plants appears to have contracted Mosaic virus (showing stunted mottled leaves) I should think from aphids early on. While the young cucumber is growing well, I thought the plant best removed.
Week 23-26: June 5 - July 2
Project 1 - Giant Onions
The weather has been changeable to say the least during this period. A sunny, hot start followed by a cool, grey and windy period, then a heatwave of 30°C and above around the summer solstice leading into very cool and wet conditions. I’ve set up a second air cooler to blow onto the best CANNA Coco Professional Plus and soil grown plants in the top tunnel and in the greenhouse during the hot periods.
In the first half of the month I watered the CANNA Coco grown onions with CANNA Coco A & B, RHIZOTONIC and CANNAZYM in water adjusted to EC 1.2 - 1.3 and a pH of 6. I have now increased the EC to 1.5 and reduced the pH a little to 5.8 to try to ensure high nutrient exposure during the maximal growth period for the onions. Although I don’t feed the onions grown in soil, I have attempted to reduce the soil pH by reducing the pH of the water added to the pots to 6.5 (my mains water has a pH of over 8.0). All plants are healthy, but I’m having to remove a few soft brown skins down to the root plate, more so on those grown in Coco than those grown in soil. The onions grown in Coco are smaller in circumference and have less green leaves.
The heatwave coincided with the appearance of spider mites in the greenhouse. This isn’t entirely unexpected as spider mites multiply fast in hot dry conditions, but it does mean that I have had to resort to spraying weekly using an insecticide with a different chemical each time, with the hope that they do not become immune to them. Also rubbing each leaf to remove the worst of the infestation. This has had the side effect of killing the predators that I introduced in March to control thrips. I will have to consider whether to re-initiate the use of these predators this season. I have now introduced specific spider mite predatory mites (Phytoseiulus persimilis) into both the tunnels, which have not been sprayed with insecticide, and they should keep the onions here clear of spider mites at least until the next heatwave.
I’ve had to tie the Coco onion in a movable pot upright, it is skittle shaped and seems reluctant to bulb. I am also having a similar problem with one in soil in the greenhouse.
Although I prefer to grow my giant onions in pots of 120 to 150 litres, I have tried one this year in CANNA Coco Professional Plus in a pot volume of 50 litres. This plant is growing well with less leaf tipping than the larger pots of Coco, however in terms of bulb diameter it is still behind the plants grown in 120 and 150 litre pots. The 50 litre pot onion is mostly being watered to run through, whereas the larger Coco pots seldom are.
The best high necked Coco onion is 26 inches in circumference, but ideally should be high necked and 28 inches in circumference by now, the world record Onion had a high neck and was 32 inches in circumference in September of it’s growing season.
Photo 1: Greenhouse onion
Photo 2: Best onion?
Photo 3: Moveable pot
Photo 4: On left, onion in 50 litre pot
Project 2 - Giant Cucumbers (Heavy)
As with the onions the weather has been extreme, but the cucumbers which are all growing in Coco in my high tunnel are faring well in the heat, with shading from the fierce sun provided by movable boards, (I’m only able to use these while the plants are small). In the first half of the month I watered the CANNA Coco Professional Plus grown plants with CANNA Coco A & B, RHIZOTONIC and CANNAZYM in water adjusted to EC 1.2 - 1.3 and a pH of 6. As the leaves are very pale I have increased the EC to 1.5 and reduced the pH to 5.8. The plants are needing much less water during the recent cool and wet conditions and I have noticed that watering during the cooler weather has been followed by the leaves exuding lots of water droplets, “guttation “ however I am continuing to water to provide the plants with adequate nutrients at this time. So far there is little indication of substantial leaf edge scorching. All plants are now tied up and I am removing flowers and side shoots as they appear. The plants are perhaps 10 days more advanced than they were at this time last year but I did start a week earlier.
Photo 5: Right hand side bed
Photo 6: Left hand side bed
Week 18-22: May 1 - June 4
Project 1 - Giant Onions
Weather generally has been sunny but with temperatures being too high (30 oC) at times. Supplementary lighting has been on in the morning only but now all lighting has either been removed or is not being used. I have installed a small domestic air cooler in the greenhouse to blow cooler air over these three bulbs.
I am watering every second or third day but not to run through (EC 1.2-1.3, pH 6.0 – 6.4).
Growth has been steady but the coco plants are now measuring smaller than the soil ones generally but particularly in height and still have a slightly lower leaf count (even though leaf size and colour is similar). It is however a marathon not a sprint so we will see what happens in time. Still some tipping problems this month in all areas, and the coco plants have more yellow stripes down the older leaves than the soil ones and this is leading to earlier loss.
Despite the early hot weather the plants look healthy. The plant in the 50 litre tub is doing okay and must be full of root now and needs as much water as the larger pots. I am still trying to prop the moveable plant upright as it seems unable to support itself.
Photo 1: first tunnel
Photo 2: top tunnel coco grown plant (L) and soil grown plant (R) now outside
Photo 3: onion in 50 litre pot
Project 2 - Giant Cucumbers (Heavy)
After growing a personal best last year in CANNA Coco and winning at Malvern with the Heaviest Cucumber, I was eager to start. I started three different strains of seed by chitting in the airing cupboard on May 15th. All had germinated within two days and were planted into 60 mm pots and placed in a propagator before moving to the greenhouse bench on May 23rd as the cotyledons opened.
On May 24th I filled six large shallow trays in my high tunnel, each with 100 L of CANNA Coco Professional Plus. Each tray was watered with Coco A & B and allowed to settle before planting the young cucumber plants the next day. The coco surface was covered with black & white polythene to retain moisture/reflect light. The weather has been hot (25 oC+) and sunny and therefore I have been shading the young plants from bright sunshine.
Photo 4: Planting
Photo 5: Half the tray set up
Photo 6: Growth so far
Week 14-17: April 3 - April 30
Project 1 - Giant Onions
The weather generally has been sunny, cool and dry but with cold nights. As per week 9 to 13 growth period, supplementary lighting has been on morning and evening when required but has been switched off manually during sunny periods in the day.
As per the additional lighting, I continue to supply supplementary heating so that temperatures do not drop below 11 oC but generally need to do so less frequently now. Day time temperatures are generally maintained at around 22 oC and with full ventilation I try to make sure day time temperatures do not exceed 30 oC in full sun.
As per week 9 to 13 growth period, watering continues to be every second or third day but not to run through (EC 1.3 to 1.6 and pH 6.0 to 6.4).
Growth continues to be steady with the CANNA Coco plants measuring larger than the soil ones generally. However I am still finding they have a slightly less leaf count, even though the leaf size and colour is generally similar. I have also observed that the Coco plants have more yellow stripes down the older leaves than the soil ones do and this is leading to earlier loss.
One plant has been leaning backwards for some time and further leaning is encouraged by the leaf weight. I am trying to prop it back upright but this will take a though weeks to fully move.
Photo 1: little greenhouse
Photo 2: first tunnel
Photo 3: top tunnel with coco grown plant (L) and soil grown plant (R)
Photo 4: onion in 50 litre pot
Week 9-13: February 27 - April 2
Project 1 - Giant Onions
The weather for March started dull and cool but most of the month has seen mild conditions albeit still cloudy. As a result, supplementary lighting has been on morning and evening but has been switched off manually during sunny periods.
Electric heating has maintained a minimum temperature of 11 oC and day time temperatures have reached a maximum of 30 oC in full sun before fully ventilating. Watering has been carried out every second or third day but not to run through. EC has ranged from 1.3 to1.6 with a pH between 6.0 and 6.4.
The plants have clearly been taking up more water with the higher temperatures and longer days.
Growth has been steady with the CANNA Coco grown plants generally measuring larger than the soil grown ones. However, I have observed that the coco grown plants do have a slightly lower leaf count, even though the leaf size and colour is similar.
No problems with tipping this month
So far so good, the plants look healthy and white roots can be seen at the bottom drainage holes of the 130 litre pots.
I also have an onion in a 50 litre pot as a trial. It looks good but it must have almost filled its pot with root by now.
This months coco plants:
Photo 1: little greenhouse
Photo 2: first tunnel
Photo 3: top tunnel with coco grown plant (L) and soil grown plant (R)
Photo 4: onion in 50 litre pot
Week 5-8: January 30 - February 26
Project 1 - Giant Onions
The past month has been very grey, dark and cold so all plants have needed almost constant heating and supplementary lighting. It's expensive but without it little growth would have been achieved.
- Early Feb
- - Transplanted a further two plants into 130 litre pots in CANNA Coco Professional Plus.
- - One plant placed on a wheeled base with the idea being to move it outside during summer heatwaves
- 08/02/2017
- - Additional two plants transplanted as per above
- 14/02/2017
- - Transplanted additional plant into Coco from a 270mm pot into a 50 litre pot. In the three areas I now have a total of 7 onions planted out in Coco.
I am watering all plants every second or third day with pH around 6.4, EC 1.4. Most times slight run through occurs after a few hours but each pot has a tray and so the run-off is being taken back up in time.
Now that I am watering more frequently, the tipping problems seem to have cleared. However I am a little concerned that the onion bulb is sitting in wet compost all the time which may cause problems later in the season.
The foliage is now a darker green colour almost like the plants in the standard peat based potting compost. However, the Coco grown onion plants are still larger and are looking strong.
Week 1-4: January 2 - January 29
Project 1 - Giant Onions
With 2016's CANNA project barely finished, 2017's Giant Onion project was off to a nice early start with the onion seed being sown on 10th October (2016).
- 10/10/2016
- - Seed sown
- 17/10/2016
- - Germination complete - 24h lighting provided
- 23/10/2016
- - Potted into 60mm square pots
- 04/11/2017
- - Potted into 100mm square pots in peat based compost + silver sand.
- 12/11/2016
- - Selected a few of the strongest plants, teased off some of the peat compost and planted into 125mm round pots in CANNA Coco Professional Plus.
- - Watered in with CANNA Coco A & B (awaiting RHIZOTONIC).
- - Fitted three support canes and clips.
- 23/11/2016
- - Reduced T5 lighting to 9.5 hours during the day but retained plants in grow cabinet as very cold weather.
- 10/12/2016
- - Moved plants into greenhouse growing area inside a cabinet under 9.75 hour T5 light.
- - Potted on into 225mm pots.
- - Watered in with CANNA Coco A&B, RHIZOTONIC and CANNAZYM. pH at 6.0.
- - Plants stood on a heated mat, which is the only form of heating in this cabinet at night.
- - Coco grown plants appear pale and drawn but now they will receive some natural light so this may change. Note: Currently using pH minus Bloom (phosphorous based), awaiting pH minus Grow (nitrogen based).
- 24/12/2016
- - Transplanted one coco grown onion into a 130 litre pot inside my heated greenhouse under T5 lights.
- - Two onions growing in a standard peat based potting mix.
- - Coco plant is larger. Watered the Coco to run through before planting.
- 16/01/2017
- - Planted one onion into 130 litre pot inside my heated tunnel under HP Sodium light with T5 side lighting.
- - Again primed the Coco first (pH 6.0, EC 1.3)
- - Potted on other plants from 225mm into 270mm pots (still in my greenhouse growing area)
- - Coco plants are larger than peat based potting mix plants
- 31/12/2017
- - Yellow tipping still evident on the greenhouse coco plant but I think it is growing out.
- - Increased watering frequency seems to help
The plants growing in Coco Professional Plus have made an impressive root system (see photo), I hope this means bigger bulbs later on!
I am finding that I need to water all the Coco plants every other day but not always to run through.
