Ripening tomatoes 08/04/08

The tomatoes have begun to ripen, the green chlorophyl in the fruit begins to dissipate allowing the red pigments to show through. As well as red pigments coming through, i noticed some yellow speckaling. It is not well understood why this occurrs but it is known that increasing the difference between potassium (K) and phosphorous (P) from nitrogen (N) will reduce the speckaling. I added a bloom boost additive that is made here called vitalink buddy, i applied it at 1ml per litre then added my general bloom nutrients till i reached the correct EC.

Hormones control the fruits ripening process, a hormonal gas called ethylene is released as the fruit ripens, this gas promotes ripening in the plant. As more fruit begins to ripen more ethylene gas is released and so becomes more concentrated until there is a flury of ripening fruit. Bananna plants release alot of ethylene gas and are commonly used in commercial fruit crop production to speed up the ripening process. We have our own bannana plant in the greenhouse and it seems to be doing the job.

In the later stage of ripening sugar production (brix formation) is concentrated in the fruit. The sugar attracts water to the fruits cells by process of diffusion, this causes the fruit to become ripe, juicy and sweet tasting. As the fruit matures, the pectin which holds the cells together begins to break down, the cells are not so structurally strong and so the fruit feels much softer.

This bunch of tomatoes are fully and evenly ripe, they are big, colourful, sweet and juicy.

Tomato training 20/03/08

With day length, sun light radiation and warmth increasing as the season moves into spring, the plants in the greenhouse have had explosive growth rate to say the least.
The picture of the floridity tomatoes in the NFT system shows how vigorous the growth has been. In order to cope with the rate of growth from the plants they need to be maintained and trained.

When the tomatoes have grown too tall for their support they are lowered by releasing the spool of string they are attatched to for support. A plastic clip is attatched to the string at the hinge and clips around the stem to support the plant without being too tight restricting the expansive growth of the stem.

As i lower individual plants i also move the support spool to the next hanging site. In effect this causes the plants to coil round at the base. With the lowering of the stem foliage at the bottom of the plant builds up at the base of the plant, this foliage is removed by cutting leaf stems as close to the main stem as possible, this will allow the plant to heal most efectively reducing the risk of infections.

Setting up a Hydroponic NFT Multi Duct- 15/02/08

This Hydroponic system is a large NFT 'table' made by Nutriculture and is know as the 601 Multi Duct. These systems come in various sizes and configurations, this 601 is about 2m x 1m with a 125L reservoir. With this system a submersible pump (maxijet 500) is positioned in the tank at the drainage end and pumps nutrient solution up the middle of the tray through 1/2" supply tube where it splits at the top through a tee piece into 4 outlet fittings (2 x tee's and 2 x elbows) where the solution enters the top of the tray. From here the solution flows down the tray and drains back into the tank. The tray is supported by a stand at the top end and the tank at the drainage end giving the table a slope of 1 in 50. This type of recirculating hydroponic system is great for growing all types of plants, I'll be using it this year to grow my favorite mini plum tomato called 'Floridity'.


After setting the system up and fitting all the pipe work i run through a solution of Hydrogen peroxide at a dilution rate of 50ml per 10L for about 4 hours. This will sterilise system killing any bad bacteria that may be lingering from last year. Once the system is clean i lay down the spreader mat which helps to keep the flow of nutrient solution even down the table.






Now i fill the tank with water and add Vita-Link 'Easy Grow' at a EC of 2.0 and pH of 5.8. Once the tank is well mixed i turn the irrigation pump on. The Nutrient solution will flow quite rapidly if you have the pump on full so it has to be adjusted down using an inline flow control tap which i position near the pump in the tank. I turn the tap to adjust the flow rate so the solution lands in the first channel as shown in the picture. Once the flow rate is set i leave the pump running 24/7.


Now the system is running i get it ready to be planted into. Using a black corriboard i cut holes out where i want my plants to be. Notice i stager the planting to allow good water flow down the table. Once the holes are cut i cover the whole table and tank with black and white sheeting (white side facing up) to help insulate by reflecting and light away from the root zone and tank. I cut an X on each hole to allow the plants to be planted through the black and white.





On planting i have tied the roller hook string around the 4" blocks like i have when i set up the 604 gro-tank with the cucumbers and hung the hook from the roof supports. This will allow me to train the vine up the string for support. Now the plants are in and the nutrient solution is flowing all i do now is monitor the solution in the tank every few days to keep the pH and EC in range. As the nutrient solution is recycled i expect to completely change the solution every 7-14 days. Cant wait for my first harvest which i expect will be in 8-10 weeks!

Rockwool Drip System - 12/02/02

The tomato plants are now firmly rooted in, a light twist of the 4" block shows they strongly held to the slab. I have removed the canes and strung the vines up with the roller hooks. Now the plants are ready the drippers are inserted into the block and i set the digital timer for the irrigation pump to come on for 3 minutes every 2 hours while the lights are on or sun is up. I set the first irrigation to come on 2 hours after the lights come on and the last 2 hours before the lights go off. On these first and last irrigations they get 6 mins.

The nutrient solution being given to the plants now is Vita-Link 'Easy Grow' at an EC of 2.5 and pH of 5.8. The general rule of thumb for drip systems is 'transpiration before irrigation' so i start the irrigations 2 hours after the lights come on knowing at this point the plants are taking up nutrient solution for the slab. I make sure on each irrigation that some solution drips out the slab, this run off wants to be around 20-40% of the input volume so if you give a slab 1ltr you want to see around 200-400ml of run off. The easiest way to check you getting enough run-off is by time, if your irrigation length is 3 mins then you want to see the slab getting run off after about 2 mins after the pump comes on. The picture shows the high pressure filter set in the nutrient reservoir, i keep the overflow valve open slightly so on each irrigation the soultion will mix and aerate.

I have covered the run-off tank with some black plastic corriboard to prevent algae growing in the open water. All i have to do now is make sure the reservoir is topped up with nutrient solution and empty the run-off tank once a week.

Rockwool Drip System - 08/02/02

3 days since planting onto the slab and the tomatoes are doing very well. At this point I give them each 300ml of nutrient solution at EC 2.2 and pH 5.8. A small amount of run-off drained out the slab on doing this.



I have placed a support cane in the block to prevent any plants from falling over. I will get round to using the roller hooks over the next few days. With the roller hooks the string is tied to the aqua tray and goes up to the roof where the wheel and hook rest on a support bar. This allow the vine to be supported by the string and lowered when they get to too tall.




At this stage it is very important for me to maintain a relative humidity within the greenhouse of between 60-75% with temperatures reaching a maximum of 25-26C. This environment will enable the plants to set off well without being under any stress through excessive transpiration (water loss). The day lengths are still being extended to 14 hours of light using 2 x 400w metal halide lamps.

Setting up my Rockwool Drip System Pt 2- 05/02/08

Setting up the pipe work for the drip system is fairly quick and easy. Make sure you have a kettle on standby as every barbed fitting you push over rigid plastic pipe needs to be heated in hot water first. This makes the pipe hot and so expands allowing the barbed fitting easily slide over, when the pipe cools it sets around the barbs making it a good water tight fitting. With the compression fittings the blue insert is barbed and is then tightened by screwing the sheath to the cap. I start the pipe work at the far end with the stop end. The piping in then cable tied to the support bar all the way along. From the support bar the the supply tubes goes through 3 elbows and up to the filter set in the 220L reservoir.

Once the supply tube is in place and attached to the filter set I can start to install the drippers. Using the hole punch I cut out the holes carefully.






Once the hole is cut get the pre assembled dripper and insert it into the tube. You should hear a 'click' as it goes in. Once in pull the compensator back while squeezing the supply tube. This will help form a tight seal. I use 1 dripper per plant some growers use 2 or more but this is not necessary.


Now all the pipe work and drippers are in place I now position the plants on the trays. I am using 2 plants per tray in the middle and 3 plants per tray on each end. Last year I put 3 plants in every tray and I found the plants in the middle of the system did not do well as the were mostly in the shade.

Once I get the spacing and positioning right on the upside down slabs I mark out with a permanent pen on the slab bag where the drainage slits will be cut. I also mark on the aqua tray where the plants will get placed.

When I cut the drainage slight I'm careful not to cut into the rockwool slab. The drainage slits need to be diagonal and between plants not underneath them.




Once the drianage slits are cut its time to flip over the slab. You may notice I have cut the slit to fill the slab at the top of the tray instead the bottom. This is not a big mistake, all I have to do is flip the slab round so the horizontal slit is at the drainage end. Once the slab is flipped it will drain some more.




When the slab stops dripping its time to plant on. I cut an X on the slab and lift up the flaps. The plant is then placed on the slab and about 200ml of nutrient solution is poured through each block. This will be the last irrigation they get for 3-4 days as the slabs and blocks hold all the solution they need.




Over the next 3-4 days the roots will find their way into the slab and a light twist of the block will show you how well the plant is rooted in. In 1 week it will fell very solid on the slab and the drippers will go in to start irrigating the slabs. I will also make a cover for the catchment tank to prevent algae growth.

Hanging above the drip system is 2 x 400w metal halide lamps. The lighting system I am using is the 'Aurora Gemini' with 'Rising sun' reflectors. This system has 2 ballasting units in one case. The unit also has a built in contact relay so all I do is set the timer on the ballast and plug it in using 1 plug. Save on valuable plug points and is neat and tidy. The lighting extends the day length to 14 hours of light coming on at 7:00am and off at 21:00pm