Campaign: Diary of a cucumber grower

Diary of a cucumber grower

Week 37-38: Sept. 12 - Sept. 25

Project 1: Cabbages

It's been a really interesting year growing with CANNA substrates and nutrients and many lessons were learned. So after several mistakes and the odd bit of misfortune I did manage to get some cabbages to the Malvern show. I entered two cabbages into the competition, one from soil and one from coco. The DWC grown cabbage was displayed on the CANNA trailer. Whilst the DWC one had a very solid heart to it, it did lose leaves earlier in the season as a result of the combination of high temperatures and high an EC. However, I know this one will do very well next year once I change a few things here and there.

As expected from the look of cabbages, the soil grown one took first place in it’s class with a weight of 40.8kg. The coco cabbage weighed in at 28kg, but as per the DWC cabbages, I know there is potential for this to be much better when I change a few things here and there in 2017.


Not my best result this year with the watermelon, but I did manage 3rd place with a weight of 18.64kg.


I also managed 2nd place for the heaviest cucumber. It came in between the two CANNA grown cucumbers from Peter Glazebrook who won 1st place and Peter Geyelin who came in with a commendable 3rd. 1st, 2nd and 3rd place weights were 11.98kg, 10.92kg and 8.48kg.

Week 35-36: August 29 - September 11

Project 1: Cabbages

With only two weeks until the show at Malvern and it is getting exciting now! I still have three fairly good cabbages that I am hoping will hold.

For the remaining two DWC cabbages, I have cut the feed right back to an EC of 1.0. This was done in an effort to keep them green, as I think if I push them further then they will split before the show. I definitely think that a later start is required for DWC grown cabbages since it’s like having rocket fuel under them compared with the usual soil grown ones.

Best remaining DWC cabbage

When it comes to my best coco grown cabbage I am very pleased. It has a large head and will certainly be good to show in two weeks time.

Best remaining coco cabbage

Project 2: Cucumbers

It's finally come to the stage where the cucumbers have slowed down and are just hanging around waiting until the Malvern Show on the 24thand 25th of September. The best one is a good size!

DWC grown cucumber for the heavy category

Project 3: Watermelons

My watermelon is still growing well and as with all the other lines it is just waiting to get to the show!

Developing DWC grown watermelon

Week 33-34: August 15 - August 28

Project 1: Cabbages

I started this project with 12 cabbages grown three different ways. That is, four grown in a Deep Water Culture (DWC) system, four grown in coco and four grown my usual way in soil in the ground. From these 12 cabbages I will be selecting the best for showing at The Malvern Show and it so happens that the best three are comprised of one good cabbage from each method (x1 on coco, x1 in soil and x1 by DWC). Therefore in terms of performance, the percentage is the same in all three methods. There are however other cabbages but we are after the biggest!

Of the DWC cabbages, I am now down to just two remaining. As expected, the biggest one split this week. The heads are very dense and solid and so should weigh heavy.

Best remaining DWC cabbage

Of the coco grown cabbages there is a really good looking one in this batch. The head is not as dense as the DWC cabbage but it does look like it will keep growing and will hold well until the show. Assuming it is still ok then I will be bringing this one along to the weigh off.

Best remaining coco cabbage

Project 2: Cucumbers

The cucumbers have started to turn yellow but are still growing, albeit slowly. I have entered one in the heavy class of the show.

DWC grown cucumber for the heavy category

Project 3: Watermelons

My one and only watermelon has progressed very well over the past two weeks and is still growing. I am keeping the EC at 1.2 with CANNA Aqua Flores and the reservoir does not alter very much at all and is easy to keep constant.

Watermelon on 28th August

Week 31-32: August 1 - August 14

Project 1: Cabbages

Due to the extremely fast growth of the DWC cabbages I think that they will be past their best by the Malvern Autumn Show in late September. As they have also lost a lot of outer leaves in the recent heat they wll not be as heavy as they could have been. I am aware of mistakes I have made along the way but am so impressed with this way of growing that I am sure that one day that it will break a world record (or two). I just need to figure out how!

Things to change when growing cabbages by DWC in 2017:

  • Seeds started far too early, I will wait another month next year.
  • The pallet supports do their job well but I think they have limited the airflow around the lower leaves. Next year I will support them with some sort of steel ring just around the base of the cabbage so that the leaves can hang free and get more air.
  • Cabbages don’t like heat, I need to remove the tunnel sheet in early June.
  • I also think that I overfed and that an EC of 1.2 is plenty for the cabbages. In my opinion an EC of 1.6 was pushing too high for a long season plant.

Coco grown cabbages (left) and DWC cabbages (right)

As for the coco grown cabbages I am now starting to have more faith with these and they actually look like they will get to the show at the end of September. As per the DWC grown cabbages, some mistakes were also made along the way. In 2017 I will try again and have already started a list of how to do things better:

  • I was under watering right from the start.
  • The irrigation set-up needs to be re-thought, especially to give me access to the coco to measure EC and pH in the medium.
  • I need to feed slow and steady rather than a high EC.
  • Support the cabbage in the same way as described above with the DWC cabbage (do not use pallets).

Project 2: Cucumbers

The cucumbers are going well and the best one is currently 17” long now and a has lovely dark green colour. Again I have made some mistakes with these plants and fully intend to repeat this grow again next year. The biggest mistake was concerning the climate as a result of setting up the plant next to the door! This results in big fluctuations around the plant in both temperature and relative humidity.

So far so good with a 17” long cucumber grown by DWC

Project 3: Watermelons

I started with two watermelon plants but am now down to just one plant as the other just gave up and wilted. The remaining plant is doing very well and I have thinned the plant down to one fruit which is now making rapid progress. For example the first picture below was taken on the 10th August and the second photo shows growth obtained just four days later on the 14th August.

Watermelon on 10th August

Watermelon on 14th August

Week 29-30: July 18 - July 31

Project 1: Cabbages

Over the course of the last two weeks I lost one of the DWC cabbages since it went to seed. I think this was due to the overfeeding in combination with a short period of hot weather. On the bright side it has given me a chance to inspect the roots. As you can see they look fantastic and have almost filled the 50L bin! Moving forward I have decided to keep the remaining DWC cabbages at an EC of 1.2. Maybe it's not a brave strategy but I prefer to play it safe to ensure at least one cabbage can be taken to a show. As all of the cabbages (7 out of 8 remaining) have suffered in the heat this has resulted in the loss of several outer leaves. In competition terms, the loss of a leaf results in a loss in weight and so this is a bad thing.

The root system of a DWC cabbage plant

Cross section of root system of a DWC cabbage plant

The coco grown cabbages have improved this week and the hearts are beginning to form. As per the DWC cabbages I am also keeping these at an EC of 1.2.

Coco cabbage beginning to hearten up

Project 2: Cucumbers

The giant cucumbers are growing well now and one has a fruit on it which is forming nicely. As you can see I have started to provide support around the stem of the cucumber since there is no point growing a giant cucumber only to have it snap off the vine before it's done growing. You might also notice that I do not allow side vines to form on the plants as these are pruned off straight away.

First cucumber to be set with support around the stem

The plant that was damaged a few weeks ago now has a very nice looking female flower on. When selecting a baby cucumber for growing on I like to look for the long thin cucumbers.

Baby cucumber on the previously damaged plant

Project 3: Watermelons

The watermelon plants continue to grow well and I have several baby melons on them this week. Unfortunately the earlier baby melons were all misshapen and so I removed them. I am hoping that my patience will pay off!

Baby watermelon

DWC grown giant watermelon plants

Week 27-28: July 4 - July 17

Project 1: Cabbages

Over the last two weeks the weather turned very hot and the DWC cabbages are now beginning to look dull. Partly due to the heat but I also think it's due to the EC being at 1.6.

After speaking to Peter at CANNA, he has explained that high EC levels correspond to high nutrient salt levels. If the EC level is too high (too many salts in solution) then the plant struggles to take water. An EC level of 1.6 may or may not be too high for cabbage in normal weather but in hot weather it most likely is. In hot weather the plant transpires more and so needs more water. But if the EC is too high then it struggles to take what it needs. So, in response to the hot weather, perhaps I should have lowered the EC to compensate for the plants increased transpiration.

I have now eased the EC back to 1.2 and hope that they start to recover.

DWC Cabbage (Nutrient: CANNA Aqua Flores A & B)

The coco grown cabbages are looking similar to the DWC cabbages but also show a lot of leaf tip burn. Apparently the ease of water uptake for a plant is easier when in coco than when in soil but it is even easier for a plant when grown by DWC. This is why the coco plants show some leaf tip burn whereas the DWC plants did not.

Coco (left) and DWC (right) Cabbages

Project 2: Cucumbers

The cucumber plant which dried out as a result of the tap not being turned on is now looking a lot better this week and is showing a lot of new growth. The roots for both plants are beginning to fill the bins and are looking healthy and white.

Project 3: Watermelons

As you can see the watermelons have really appreciated the hotter weather and have gone crazy. I have now switched the feed from CANNA Aqua Vega to Aqua Flores and am feeding at an EC of 1.2. This EC does not seem to vary very much which is strange as the cabbage take a lot more feed out of the solution. Female flowers not setting yet.

Week 25-26: June 20 - July 3

Project 1: Cabbages

As mentioned in the previous report, I decided to increase the EC of the DWC grown cabbages since they were consuming a lot of nutrient. Having increased the EC to 1.6 they continue to be using a lot of feed but also continue to grow well. I also increased the EC of the Coco grown cabbages to 1.6 and they are also doing well.

DWC Cabbage (Nutrient: CANNA Aqua Flores A & B)

Coco Cabbage (Nutrient: CANNA Coco A & B)

Project 2: Cucumbers

Disaster struck with one of the cucumbers plants! When I was changing the reservoirs of feed for the watermelons and cucumbers this weekend, I forgot to re-set one of the cucumber taps before going back to work and this is what greeted me on my return:

Wilted giant cucumber plant

I have since lost the growing tip of this cucumber plant but it has started to produce a side vine. This side vine will grow on and be trained as the main vine. It's a setback of course but all is not lost! The other cucumber plant is growing happily since there was no limitation in water for that one. It is showing the first signs of female flowers.

Project 3: Watermelons

I am continuing to feed with CANNA Aqua Vega A & B with the EC at 1.2. The EC in the tank remains steady and I am not having to add any feed at the moment to maintain this. I have seen the first signs of female flowers on the watermelons and am hoping that they will be pollinated soon.

Week 23-24: June 6 - June 19

Project 1: Cabbages

Over the last two weeks the DWC cabbages have continued to grow well. The pH of the nutrient solution is now stable since I changed to CANNA Aqua Flores A & B. I maintained the EC at around 1.2 but am thinking about raising it up to about 1.6 as they are using a lot of feed every day.

The coco grown cabbages have also picked up a lot since I increased the watering and this also tells me that the limitation in growth was clearly due to a lack of water and nutrients. I may also increase the EC of the Coco A & B feed in the next week or so.

The soil grown cabbages in the ground are still looking slightly bigger than the coco cabbages.

DWC Cabbage (Nutrient: CANNA Aqua Flores A & B)

Coco Cabbages (Nutrient: CANNA Coco A & B)

Soil Cabbage

Project 2: Cucumbers

The cucumbers (also grown in DWC and currently fed with CANNA Aqua Vega A & B) are growing slowly following the move from the warmer greenhouse to the tunnel. I realise I have made a mistake in placing them too close to the door! The weather has been cold and windy and they certainly don’t seem to have appreciated it.

Project 3: Watermelons

The water melons are vining well now and the first male flowers are appearing. I am continuing to feed with CANNA Aqua Vega A & B (EC: 1.2) and the pH remains stable at 5.2.

Week 21-22: May 23 - June 5

Project 1: Cabbages

The DWC cabbages grown with CANNA Aqua are still fantastic! Over the last week, the pH started has to drop quickly each day. Apparently when the pH drops in this way it 'can' be an indication that the plant is in the flowering stage since uptake of the flowering nutrients (e.g. potassium) causes the pH to drop. This can be a good indicator of what the plant requires, fascinating stuff and I am learning new things every week. Over the last week we (CANNA and I) decided to switch to CANNA Aqua Flores and that has resulted in the pH becoming more stable. The cabbages look better too and are a lot greener!

On the other hand I am still making big mistakes with the coco grown cabbages, and they are still showing leaf tip burn, which I think is a case of under watering. I have increased the amount of water now which also means I have more running to waste. I don’t like waste and was trying to be over careful I think! As a result the normal soil grown cabbages in the ground have now slightly overtaken the coco grown cabbages.

As per usual, a selection of comparison photos: left hand side photos were taken on the 29th May and the right hand side photos were taken on the 5th June.

Project 2: Cucumbers

The cucumbers are now plugged into the same system as the watermelons and so are receiving the same feed. So far they look healthy. I have covered as much of the pipe work and dustbins as is possible with white plastic to reflect the light away and keep the water and roots cool.

Project 3: Watermelons

The watermelons have really taken off over the last 7 days and you can now see the vine forming and side shoots developing from it. They are being fed with Aqua Vega at an EC of 1.2 and pH of 5.2 and look to have good root development.

Week 19-20: May 9 - May 22

Project 1: Cabbages

I am still very pleased with the cabbage progress although I had a bit of a problem with the coco grown cabbages. The water timer stopped working for 4 or 5 days and I did not realise until the cabbages started to exhibit purple colouring and one of them also picked up a bit of tip burn. Quite a lesson learnt….”keep an eye on the timer!”

The DWC cabbages are really growing fast now and the pallets are nearly all covered. For the coco grown cabbages I have been keeping the coco A&B feed EC at 1.4 and for the DWC cabbages I have been trying to keep the Aqua Vega feed at 1.4 also but it drops fast every day. I have therefore been topping up the reservoir every morning with varying amounts of feed.

The soil grown cabbages (see below) have also greened up and are growing well although they are smaller than both the Coco and Aqua cabbages. So far, the cabbages in order of size are: Soil < Coco < Aqua.

To give an idea just how fast the CANNA Aqua grown cabbages are growing I have included some comparison photos again. On the left are the cabbages as of the 15th May and on the right as of the 22nd May.

Project 2: Cucumbers

I have finally started the cucumber seeds for project 2. I started to chit them on 15th May and within 24 hours they had roots! I am growing two plants with one seed from my World Record Cucumber (2015) and one seed from the parent that grew that World Record Cucumber. Both seedlings are now in a DWC setup and the picture below shows one just after popping out of the CANNA Aqua clay pebbles.

Project 3: Watermelons

So far the watermelons are very slow but that is a normal start as the nights have been cool and they don’t seem to like that. The root spread is good and I still have the Aqua Vega feed at an EC of 1.0, which I will increase once they get going.

Week 17-18: April 25 - May 8

Finally the weather has warmed up and I can now see a lot more growth in the cabbages. I have netting all around the tunnel from the roof down to just above ground level to keep the pigeons out. However I did have a problem with them this week. Whilst we are lucky enough to live in the countryside and enjoy a lot of pheasants wondering around the garden, they can cause trouble. This week one of them figured out that he could walk under the pigeon netting then jump up onto the cabbages for a good feed! He (or she) sampled three of them but luckily didn’t touch the biggest one! I have now fully netted the cabbages and hope to keep the pheasants out.

I have increased the EC of the feed for both the DWC and Coco cabbages to 1.4. The DWC cabbages are using a lot more feed now that the weather has improved. The watermelon setup has been moved to its final position in another tunnel. They now have some true leaves but are still very slow, although in soil I also find them slow to start and so am not too concerned at the moment. I am still feeding the watermelons at an EC of 1.0 with CANNA Aqua Vega. The cucumbers will be started in week 19 and I will be growing two plants, both by DWC. These will be from my own World Record seed.

Below is a photograph of the watermelon setup. The second greenhouse is just to keep them warm if the nights go cold again.

Below is a selection of photographs to show the growth of the cabbages. The left hand photographs were taken on the 1st May and the right hand photographs were taken on the 8th May.

Week 15-16: April 11 - April 24

Considering the weather is cool for the time of year I am amazed at the growth the cabbages are making. I have never before observed growth like that I am experiencing with the Deep Water Culture (DWC) set-up. The plants look very healthy and I am very pleased with them.

With the Giant Watermelon project I had a setback with the grafting – it didn’t work!! So, I have gone with a couple of non-grafted watermelon plants raised in DWC. They are just at the cotyledon stage at the moment. I bought a 140 litre container to grow them in and have put together the setup as shown in the picture below. Later in the season I will join this up with two cucumber plants, each one grown in its own dustbin. The setup below is recirculating one just like the DWC cabbage. Currently I am feeding the DWC cabbage with CANNA Aqua Vega at an EC of 1.2, the Watermelons at 1.0 and the Coco grown cabbages are fed with CANNA Coco A&B at an EC of 1.2.

Week 13-14: March 28 - April 10

Project 1 – Cabbages

Over the last two weeks the DWC cabbages have really moved along. I have tried to push the EC up to 1.2 but as they are now using more feed the EC seems to be dropping a little daily. I now have a 200L header tank set up at the top end of the tunnel. It is attached to the system via a ball valve so the water level in the DWC should never drop. I will start to adjust the reservoir this week day by day.

I usually grow 12 cabbages in soil but this year I have had a change of plan and am only growing 4 this way. The soil grown cabbages were planted out on Thursday 7th April just outside the hydroponic cabbage tunnel. This will give a good indication of the difference in growth. My thoughts at the moment are that the DWC cabbages will take some beating! The picture below shows the soil grown cabbages to the side of the tunnel.

Below are a series of photographs of the cabbages. The left hand photographs were taken on the 26th March and the right hand photographs were taken two weeks later on the 10th April.

The four cabbages in coco are much slower in growth but are looking healthy.

Project 3 - Watermelons

Not a huge amount is happening with the watermelons so far. I have the long gourd rootstock in DWC and the watermelon plants in Coco Professional Plus (both fed with the corresponding nutrients (AQUA/Coco A&B) with an EC of 1.0).

The first attempt at grafting the watermelon was fiddly so I have sown another batch of watermelons as backups.

From left to right the pictures below show the watermelons in Coco, the long gourds in AQUA clay pebbles and a comparison in size between the two.

From left to right the pictures below show the centre of the long gourd being cut out, the watermelon grafted to the long gourd and finally the grafted watermelon back in the propagator.

Week 11-12: March 14 - March 27

Over the last two weeks my cabbage plants have really moved on fast. The days are getting longer and we have had some good sunny days. The cabbage plants were outgrowing my small greenhouse and so as planned, I have moved them into a dedicated tunnel. Since they do not like too much heat I have had to make the tunnel open sided. The reason to grow them under cover is to keep the leaves dry but also to stop rainwater getting in the hydroponic system or Coco substrate.

The other problem with the cabbage is supporting them. I have therefore made frames from pallets with 4 wooden legs on them. The buckets and the pots go below them and the cabbage will grow up through and rest on top. The tunnel is 10 meters long and 6 meters wide. I have spaced the cabbage at 2.3 meters apart. As you can see I have covered the floor with white plastic to keep the weeds at bay and reflect some light.

I have transplanted the Coco cabbage plants (see below) into 50 Litre pots. Since they have been moved I have been feeding (Coco A/B, EC: 1.0) them with a watering can. At present they are still smaller than the DWC cabbage plants.

Moving the DWC system (see below) was quite simple, I just extended the water pipes joining the bins to get the correct spacing. Then the supports were put over the bins and finally the supports were wrapped with plastic to keep the wind off a little.

So, now that all eight cabbage plants are in their final spot and I have increased the Aqua Vega feed (EC: 1.0 to 1.2). The photo’s below show the difference between the Coco (left) and Aqua (right) plants.

The next project to be started will be the giant watermelons. I will be grafting the watermelon plants to long gourds. The reason for this is because watermelons are very susceptible to root disease and the long gourds are not.

Week 1-10: January 4 - March 13

Project 1 Giant Cabbage (1a-Coco, 1b Aqua)

Since the cabbage project was started early January this initial report is a condensed report on first stage growth.

The cabbage seeds were started in 3.5” pots of CANNA Coco Professional Plus and were initially fertilised with CANNA Coco A/B (EC: 1.0, pH 5.5). No other additives (i.e CANNA RHIZOTONIC) were used in the first few weeks due to the delivery from CANNA being in transit from The Netherlands.

Picture 1 below shows the young cabbage plants on the 16th of January, at which point they were transplanted into either CANNA Coco Professional Plus (picture 2) or into CANNA Aqua Clay Pebbles (picture 3). The cabbage project will consist of four plants in each system.

Pictures 1 and 2 below show the Coco and DWC (Aqua) plants on the 21st of February.

The setup for the Coco plants was very simple. The nutrient solution is stored in a header tank and is fed to the cabbage plants via T-Tape. There is a simple pump in the nutrient tank attached to a timer. I am giving the plants five minutes of water per day and will increase the frequency of watering as needed.

The homemade bubble bucket setup for the DWC plants was somewhat more complex. I started with four dustbins, one header tank, a heap of pipes and fittings, four taps to drain the system, an eight outlet air pump and a water pump for circulation. After a few hours of cutting and drilling holes I managed to construct the system.

The cabbage plants are supported over the nutrient solution in net pots filled with CANNA AQUA clay pebbles. There are two air pipes per bin in the bottom of each which are constantly pumping. Water is constantly re-circulating around the system from the header tank. I am using water from the stream at the bottom of my garden (EC: 0.2) and CANNA has advised that I need to bring the EC of the water up to 0.45 with CALMAG Agent. This is because water with an EC of 0.2 is considered soft and does not contain adequate amounts of calcium and magnesium. Adding CALMAG ensures there will be no deficiencies in these elements. I then add CANNA Aqua Vega A&B to bring the EC up to around 1.0 after which CANNA RHIZOTONIC was added at a rate of 2 ml/Litre. The pH was then adjusted down to 5.5

As of the 14th March (week 11), the cabbage plants in the Aqua system are growing faster than those in the Coco system.

The Grower:
David Thomas from Cornwall has been growing all of his life after having been born into a farming family. David has always enjoyed gardening as a hobby and some 16 years ago grew his first Giant Pumpkin.

He attended his first UK Giant Vegetable show at Shepton Mallet in 1999. Seeing the vast array of Giant Vegetables on show, David quickly became hooked and has been growing Giant Vegetables in his garden ever since.

David broke his first World Record in 2011 with a parsnip weighing 7.88 Kg at the Malvern Autumn Garden Show. In 2014 David set a UK record at the UK National Giant Vegetable Show at Malvern by growing a Giant Cabbage weighing 56.4 Kg. David broke another World Record at Malvern in 2015 with a cucumber weighing 12.9 Kg.

The Project:
Until recently David has been growing Giant Vegetables traditionally in soil. However, in 2015 David became interested in growing hydroponically having recognised its potential to advance his growing. He now has the bug for this.

Having witnessed David's dedication and drive, CANNA is delighted to be assisting David to achieve his goal through the CANNA Sponsored Giant Cabbage & Cucumber Project 2016.

Growing medium: CANNA Coco Professional Plus CANNA AQUA Clay Pebbles CANNA AQUA Clay Pebbles CANNA AQUA Clay Pebbles
Plant: Cabbage x4 Cabbage x4 Cucumber x4 Watermelon x1
Location: Polytunnel Polytunnel Polytunnel Polytunnel
CANNA Nutrient: Coco A & B (5-4-3) AQUA Vega (5-3-8)
AQUA Flores (4-4-10)
AQUA Vega (5-3-8)
AQUA Flores (4-4-10)
AQUA Vega (5-3-8)
AQUA Flores (4-4-10)

With a UK Giant Cabbage record already under his belt, David will be growing 4 cabbage plants on CANNA Coco Professional Plus (Project 1a) which we believe will provide ideal root zone conditions not present in soil.

David will also be growing 4 cabbage plants hydroponically using CANNA AQUA nutrient and clay pebbles (Project 1b). A significant advantage for David of growing on a recirculating system is that it uses less nutrients and water than most other systems.

Also, because of a meticulous control of the supply of nutrients with CANNA AQUA during the growth and blooming phase of the plant, and the fact that the plants roots are in direct contact with the nutrient solution, means that the potential yield is high.

However, as always, the onus will be on David to perfect his growing with both Coco and AQUA but we will be there every step of the way to share our expertise.

Furthermore, David will also also be growing four cucumber plants (Project 2) and one watermelon plant (Project 3). These will also be grown hydroponically with CANNA AQUA in combination with CANNA additives (RHIZOTONIC, PK 13/14, CANNABOOST Accelerator and CANNAZYM).