Establishing plants into the systems

Here's an overview of the greenhouse with most of the plants just gone into the different systems. The humidifiers are going to play an important role in the early establishment stages as there will be less demand for water to be uptaken by the roots and will allow the plant to spend energy in root growth. A young plant with a healthy mass of roots will be more hardy and have a much higher yield potential.

Another way to maintain high humidity levels in the establishment stages is to use something like these propagation domes. I've used them on the IWS flood and drain and the IWS dripper systems because they are a perfect fit. They create a micro-climate where moisture generated from the pot and the plants leaves can't escape and so elevates the humidity levels inside. The vent on the top can be opened gradually to control the humidity levels, gently easing the plant into the surrounding environment. This ensures that the plant can withstand the humidity levels of the main room with minimum of stress.

On the left hand-side of this picture you can see the tomato plants in the autopot system. I've got coco fibre mixed with perlite as the growing medium but you can use rockwool cubes, mapito, serramis, fytocell or soil (anything with a good capillary action but has a good air content). At the minute the pots aren't connected to the water butt. Even though it is a self-watering system i choose to hand water for the first couple of weeks. This is because i do not want the plants to be overwatered at such an early stage. By hand watering i can allow the pot to dry out slightly before the next watering. This will increase the air content within the pot and lower the water saturation level creating a perfect environment for a young root system to grow in.

Everyone has their own ideas and methods for rooting plants in NFT systems. Working at a Aquaculture i get to hear them all and i'd say there's no set practice that will work the best everytime. What will work best everytime for one person doesn't mean it will definately work best for another. There are many irrigation patterns that people go through like 15mins on every hour and will increase the frequency as they get bigger. There are generally two types of people, people who overwater plants by either putting a plant on the system before its had chance to root properly and/or having their pump on too high a setting where it floods the tray and drowns the young roots. On the other hand you get people that try that hard to get as much air as possible to the roots by having a massive ammount of time between irrigations for a prolonged period despite having a good ammount of root mass in the block to begin with. Even though the block may feel wet still the pioneer roots that are on the tray will dry up and the demand on the plant may outweigh what is supplied to it thus stressing it and not allowing its roots to develop properly.

I've said it before that every plant has a different root system and every growroom environment is different therefore each time needs its own tweaking. I will only start with a plant that has an abundant ammount of roots in the block, that way it will cope better the environment change and ammount of water you throw at it. I've personnaly not had any problems with putting a well rooted plant on the system with a constant flow on a slight trickle. This is the way commercial greenhouses have done it for years to great success.

Aubergines in the amazon were a doddle because i didn't need to alter irrigation settings as the aeroponic method delivers an ideal ammount of water and air to the roots so i just left it sprinkling 24hrs.

Both the tomatoes on the high and low pressure drip feed systems were left to sit in pre-soaked rockwool and coco slabs. They didn't need an irrigation for a number of days. The slabs remained damp enough for up to 5 days before needing a watering, and that was only to prevent a ph or ec change. They weren't regularly irrigated till up to 2 weeks after hand or manually irrigating them. This let the root system develop so it can cope with the frequency of timed irrigations daily.

Establishing young plants 10/03/09

These are some of the young plants i will be growing, sweet peppers on the right, tomatoes in the middle and chillies to the right. There are also some plants called Pepino at the far right which are nicknamed melon pears because of their sweet soft fleshed fruits.
The plants have recently been inserted into the larger 4" rockwool blocks and have been kept under a gentle fluorescent light to let them develop their root system before intensifying the light, i'm using a T5 high output 8-way flourescent light because it produces lots of lightat a low temperature with low power comsumption and has a good spectrum of light for vegatative growth and i can choose between 4 and 8 lights. I'm keeping humidity high into the 70%'s to slow the transpiration rate. I use 2 HR50's for the whole greenhouse which is 75m2, they're linked up to a humidistat to control humidity.

As you can see the plants are sat on mesh grid this allows air to the underneath of the blocks. When roots reach the bottom and come into contact with the air the tip dies back.
Using the analogy of 'topping' a plant where you nip the growing tip off a plant to encourage side branch growth by changing the position of growth hormones in the plant. The same principles can be applied to the roots.

This technique is called air pruning and is something i will always do to get my plants established well enough to cope with environmental changes. Changes from the propagation stage to final planting position include greater light intensity, heat, air movement and amount of water recieved by the plant. Moving a plant too early will put too great a demand on it before it has developed and will stress it to the point of stunted growth, poor root development and risk of becoming disease infected. A well established plant will grow quicker and healthier and have potential to yield greater than one that isn't.

Note: All plant species and varieties among species have widely different root systems some thin some thick, some are abundant others are not.

A technique in commercial grows is to use a root-stock plant and to graft a favoured top part of a plant onto it. This means you use a variety of plant that has been bred to produce alot of roots and is disease resistant. That plant hasn't been bred for flavour or yield so to get the best of both worlds, they simply cut the top off and replace it with a plant that has been bred for flavour and yield. It's a technique i've not tried but am very interested in the benefits as you can choose the best phenotypic characteristic from two plants.

Arranging systems

With seeds sown i can concentrate on the layout of the greenhouse. Once i put a plant into a system it will be a nightmare to move it so it's best getting it right from the start. I found it took longer planning the greenhouse layout than it did moving all the systems back in.

To tackle things methodically i looked at things i would use most often. Starting off with the 350l waterbutt that i use to top up my tanks with, storing water in the waterbutt allows the water to reach room temperature and any chlorine to evaporate. The waterbutt also holds the water to both my HR-15 humidification systems. I chose to position the waterbutt in the centre against the backwall of the greenhouse because thats the least distance for me to travel with buckets of water, and both humidifiers point to either end of the greenhouse to distribute the humidity evenly and effectively.
The next choice i made was because the greenhouse is a display greenhouse i wanted it to look good when you walk in. I thought that putting the IWS Systems either side of the waterbutt would present some symmetry when entering the greenhouse. It also display the 3 sizes of waterbutts that we stock.
Last years banana plant grew massive and hopefully this year it will too. Taking this into consideration i had to position it at the far end of the greenhouse under the apex of the roof where the greenhouse is at it's tallest.
Since this picture was taken i've done a bit of shuffling around of systems. I swapped the drip system with the NFT Multi-Duct 601 because i have set the drip system up as a 'run-to-waste' systems and it makes life easier for me when it is near the door and i can run a hose out of the catchment tray.

Using a vertical grow system such as the coliseum must be positioned facing the sun when not using artificial light and again i run it to waste straight out the door.
Another thing i had to consider was planting density, which plants were off in what systems, how many plants will fit in the system and how much space will the plants require at their mature size.
It can be quite hard to visualize all those factors when your plants start off so small. I like to give myself room to manouvre around the plants but i also like the jungle look in the greenhouse.

Propagation for 2009 - 02/02/09

It took longer to clean down all the systems and paint the floor than expected, in a heated greenhouse i would have liked to have started my seeds off earlier to give them a head start to the season.

I'm propagating more seeds than whats needed just incase some of the seeds aren't viable and so i can pick and choose the better plants later on.

I've also used a selection of different propagation media incase i have better success with one and not another. I've used 1.5" rockwool cubes, fleximix, jiffy 7 peat pellets and a new media called sure to grow which is like pillow stuffing.

I pre-soaked everything with VitaLink Plantstart and BioPlus, two great products for getting well rooted little plants. I set the EC to 1.0 and the pH to 5.8.

I am using a T5 LightWave 8-Way flourescent lighting unit above the propagator and i'm really impressed by it. I can choose to have 4 lights on at once (4 middle tubes or 4 outer tubes) for when they are young and all 8 lights for vigorous growth when they are large enough.

Sometimes when the sun came out temperatures would reach above 30°C in the propagator, it was essentialy a greenhouse inside a greenhouse. To prevent cooking my young plants i used black and white reflective sheeting to reflect the suns rays away from the propagator, and lifting the light away helped. Opening the vents helps cool down the propagator but drops the humidity levels in there, I can keep an eye on my temperatures and humidity levels using a hygro-thermometer and it tells me the maximum and minimum levels of both readings.

Now i'm waiting for seeds to germinate i can organise the rest of the greenhouse.

A Fresh Start

Last year's grow was a steep learning curve for me. It ended well with lots of fruit and veg for staff at aquaculture and most of the customers who came to visit.

However there were a few problem issues such as god damn mealy bugs, it was near impossible to control these fluffly sacs of goo. They appear to be imobile but managed to get into all nooks and crannys they could find and laid hundreds of eggs that spread throughout the greenhouse carried by the wind.

As the growing year drew to an end it became a good chance to completely clean down the greenhouse and start a fresh.


I started by dismantling all the systems and cleaning them down with hydrogen peroxide, it's safe to use and doesn't leave a harmful residue like bleach can.

The paint on the floor had been annoying throughout the season and was chipping up. I attempted to bring up any loose flakes but when i realised i would be there for days lifting the whole layer off, so i decided i should just paint over it and hope for the best.

With a new lick of paint and a wipe down the greenhouse was ready to start a new growing season.

Bananarama! 01/07/08

The banana plant has reached maturity and is bearing large well formed fruit. It looks very impressive in our greenhouse standing at around two and half meters with broad fan like leaves.

As you can see the bananas have begun to ripen on the plant, time to cut down. The bunch has quite a few bannanas on it all of a decent size too.

For the bananas to ripen i kept them in a cool dark place. I utilized the mini grow tent for this. Next time i do it i will use use an extraction fan in the tent for air circulation. You could tell there was a high humidity level in the room when you opened the door, this increases the chance of any mould ruining your harvest.

The taste test - These bananas were thick and fleshy, not the best for eating raw as it gets a bit sludgey in the mouth. Perfect for cooking as a desert though because they were really sweet.

All apologies 01/07/08

To all that follow this blog, i am sorry that i haven't been able to update my posts for a hell of a long time. This summer has been a busy time for the company with hollidays and staff change. Lots has happened in the greenhouse but i will try and update you with some of the more important stuff.

I will be allocated more time, more frequently to spend updating the blog too keep you more up to date with what's goin on.

Setting up an NEF Ebb and Flow / Flood and Drain system with Pablo Beetroot 05/05/08

I have chosen to grow a variety of beetroot called Pablo for its uniform shape, smooth skin, great taste and high yield. As you can see i have germinated the seeds in jiffy peat pellets. I like these because they retain moisture well and contain slow releasing nutrients that are vital for early growth. I have brought them on until they are well established and about 10 - 15cm in height. Their leaves are weighty so i have used sandwich bag ties to hold them up by tying a loop around the stem and sticking the other end in the peat pellet.

Sit the 45 litre nutrient reservoir on a level surface and place the flood tray on top so that it sits in the grooves. position the tank so the gap faces the front. This is where you check and fill the nutrient solution. There are two tubes that stick upright from the flood tray. The smaller of the two nearest the front is attatched to a microjet mc 450 pump and allows for the nutrient solution to flood the medium in the tray.


The second larger upright tube is an overflow drain so that the flood tray can never overspill into the grow room. Handy when theres electrics about. There are also small holes in the grooves of the tray which are for drainage too.
I have added a thin layer of large 8-12mm clay pebbles to allow for better drainage.


I have filled the rest of the tank with seramis that are smaller than the clay pebbles i have used and they also hold onto more water to prevent drying out between floods.
I dug a space in the seramis to fit the peat pellet, in a staggered arrangement for maximum growth space and covered it back up with the seramis.


After transplanting the plants look lifeless and limp. This can be normal as there are stress factors such as a sudden drop in humidity and temperature from coming out of the propagator. Also because the seramis was dry when i transplanted i felt that it sucked some of the moisture out of the roots and peat pellet by process of osmosis.


I took a jug and scooped the nutrient solution i pre-mixed from the nutrient reservoir and poured it over the medium. I then made a black and white cover to prevent loss of moisture from the medium, i cut holes in the right place and pulled the plants through.


After a few days when the plants had rooted in and become established i began to flood the table once a day using a grasslin segmental timer set to 15mins on at mid day.
After nearly two weeks the beets are showing rapid signs of growth.

Setting up an Amazon aeroponics system with perpetual spinach 20/05/08

The amazon took two years of development by company Nutriculture to bring to the market a reliable product of top quality that gives high end aeroponic results at an affordable price. Aeroponics offers an optimal ratio of oxygen, water and nutrient to the plants roots which allows for rapid growth, promoting high yields. It is simple to set up and i will show you how.
Lets begin with the base. Everything will be stacked upon the base so make sure it sits on even ground, do this accurately using a spirit level or by seeing whether water builds up at one end or is evenly spread in the bottom. The base is also the nutrient reservoir and has a 50 litre capacity. Make sure the lowered groove/lip is towards the back of the tank as this is where the next tier will sit, allowing you room at the front to mix your nutrient solution.

The next teir is the base of the root chamber. It has two holes at either end, the larger should be facing the back of the system as it is a drain hole. The smaller hole at the front is to allow the delivery tube to connect to the pump.

Next we sit the already assembled delivery tube and sprinklers in the raised grooved beds to hold the in position for an even delivery of solution to each plant site, it is raised to prevent root mass building up around them and blocking them.


Twist the 'tail' end of the delivery tube so that it fits through the small hole in the base of the root chamber and hangs into the nutrient reservoir.
Here we connect the pump to the delivery tube. I have used an extra piece of standard 1/2" hose pipe to lengthen the delivery tube so that the pump sits flat against the bottom of the nutrient reservoir and gets the maximum usage out of the tank.

Now we can place the lid on top. Here you can see this is an eight site Amazon but there are 4, 8, 16, 32 site lids, and now you can double the ammount of sites with the brand new Twin Amazon that shares a nutrient reservoir (keep updated as i will post a blog on this new system soon.
Here is i have covered the amazon in black and white, this helps reflect light and heat to prevent an overly warm nutrient solution as the greenhouse is already warm. However you may want to add a water heater if you need to control your temperature.

There are two sizes of holes in the Amazon lid that hold either 1.5" net pots or 3" net pots. The 1.5" net pot sized holes are ideal when using an aeroponic propagator such as the x-stream aeroponic poragators as you can simply propogate and grow a fully mature plant without transplanting into a larger sized pot. However there is also a 3" net pot sized hole and is ideal for larger sized plants with greater root growth and stem size.
I will be growing a perpetual spinach in the amazon which i have germinated in 1.5" fleximix blocks, but for demonstrative purposes i will show you a simple method of how to transplant either a 1.5" net pot or grow cube such as rockwool, fleximix or jiffy peat pellet.

Simply insert the 1.5" net pot, fleximix, rockwool, jiffy into the 3" net pot and fill the side gaps with seramis (as pictured) or small 4-6mm clay pebbles as these are small enough to fill the gaps without spilling out of the net pot. They also provide excellent drainage preventing any rotting around the stem.
This is a picture of the sprinklers in action, they spin round supplying an even spread of nutrient solution to the roots keeping them moist but allowing maximum aeration for a fresh supply of oxygen to the roots.

Keep updated as i will post new blogs on the spinach's development.

Wind burn 03/05/08

The chilli plants have grown real tall now, so tall infact that the upper leaves are in the direct pathway of one of the circulatory fans at the top of the greenhouse. The force of the air movement causes an extreme case of evaporation of water from the leaves. Transpirational pull cannot keep up with the moisture loss and so cells in the leaf dry out. At such a level of water evaporation from the leaves it leaves behind the nutrient salts that cannot evaporate making them more and more concentrated until they reach a toxicity level.
Leaf burn usually starts with signs of upward curling of leaves. Then there are similar signs to nutrient burn with browning patches and around the edges of the leaf, deformed growth patterns. To stop further wind burn effects i am going to move the fan to another area of the greenhouse. To prevent anything like this happeneing predict the growth of your plants when deciding on positioning of a fan.

Aphid pest problem 12/04/08

I have noticed some curling and deformities in the new growth leaves of the chilli plants. These deformities have come from toxins in aphid saliva that cause mutations of plant cells, they cells around these mutated cells grow and expand, resulting in a curling effect.

When the leaf matures it fully expands and flattens out, where the mutated cells were there is now a hole because the imbalance of growth hormones of these cells don't allow the cells to form properly.






I have seen a few aphids on the lower leaves of a few chilli plants. This is not usually a problem as we release parasitoid wasps as a control regime for preventative measures.

A few aphids soon became a load of aphids, aphids are asexual this means they don't posess male or female sex organs. Infact they are born pregnant with an exact clone of themselves. You can tell which ones are mature and are ready to give birth by their size. A population of aphids can grow at an alarming rate. Our prevntative measures do not seem to be working.

Under closer observation i was able to identify the species of aphid as a glasshouse-potato aphid, they have long legs and the mix of parasitoid wasp that we were releasing were ineffective at ovipositing their young into the aphid. I ordered the correct parasitoid wasp, opened the bottle in the room and gently tapped it releasing the wasps around the plants. I noticed a difference within days.

The parasitoid wasp injects (oviposits) its fertilized eggs into the aphid which will live inside the aphid in its larval stage and will emerge from the host aphid as an adult. The aphid dies but its body remains intact but in a mummified form which is a pale colour.

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.

Chilli and Pepper Training 23/03/08

The chillies and peppers have grown to a decent height now and will need to be supported. The reason most chillies and peppers need supporting is because they have been selectively bred for the heaviest fruits despite not being able to support themselves naturally.

When supporting chillies and peppers i use string made from polythene as it doesn't absorb or hold any moisture. This quality prevents any micro habitats for bacteria and mould to breed in increasing the likelihood of plant infection.
I start off by looping the string around the stemp of the plant just before the bification of the stem where it splits into two. I tie a knot around the string itself rather than tight up to the plant. This way of tying allows the loop to expand without coming loose. This means as the stem thickens the loop will not restrict growth.

The other end of the string is tied to a beam at the top of the greenhouse. The support lines are strung up in a 'v' shape, this means as the plant branches out towards the top the foliage will not cross over each other and become a dense canopy. I've strung up two support lines for now but will increase this to four as they grow bigger. Like the tomatoes i will use the plastic clips to train the branches along the support lines as these will bear the weight of the large fruits.

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.