This hydroponic system is one of my favorite systems to use in the greenhouse because its so easy to set up and takes very little care and attention to maintain it. 'Autopot's' come in 2 variations, the 1 pot system (pictured left) and the 2 pot system (i will set up later this month). The 1 pot can be set up to one small reservoir or you can link up multiple pots to one larger reservoir as i will be doing here. The one pot module consists of a square 15l pot, base tray and lid, one 'aqua valve', 1.5m 4mm flexible tubing and 2 root control mats.
The autopot is a simple yet clever method hydroponic growing. The 'aquavalve' lets nutrient solution fill the base of the pot to a depth of 20mm, once it has filled to 20mm the valve shuts off. The plant will then use the solution in the base of the tray until there is none left, once all the solution is used the valve refills the tray to 20mm again. The is all done without the use of electricity and you dont need any pumps. This system is described as 'plant driven' as the plants uptake drives the irrigation.
The autopot comes with very clear instructions that are easy to follow. One very important factor in setting up is making sure the aquavalve is set properly. The picture shows 2 valves, the one on the right is set correctly while the one on the left is not. You can tell by the the way the float is sitting lower on the left valve than the right. To set the valve simply pull back the top float and remove the yellow rubber, clean it and push it back in firmly. Job done.
Once the valves are set attach the 4mm tubing to in and fit the valve in the base tray by allowing the raised tee on the base to sit in the half moon recess on the valve. This will allow the valve to sit securely in the tray. I'm connecting 4 Autopots to one 1ooL reservoir although this size reservoir could feed up to 10 pots without a problem. The reason i use a large reservoir is so i can leave if for long periods without having to keep topping it up. To connect to 4 Autopots to the tank i use 3m of 13mm flexible pipe, a 'Hoselock' tap connector, two 13mm>4mm 'X connectors' and one 13mm flow control tap. In the picture you can see the Hoselock connector attaches to the tap on the reservoir which is attached to the 13mm pipe. The 13mm pipe runs between the pots with the 'X connectors' in position to connect the 4mm tubing from the aquavalves to the 13mm pipe. At the end of the pipe i fit a flow control tap and keep it closed, i will occasionally open this tap at allow and residue build up in the pipe to be flushed out. Notice the reservoir is raised on a stand to use gravity to increase the pressure to the valves.
Now the pots are connected i place the root control mats in , the copper one goes in the tray copper side up and the black one goes in the pot. On top of the black mat in the pot I put a layer of clay pebbles about 3cm deep. This will stop the very base of the pot from getting waterlogged. On top of the clay pebbles i use a mix of coco coir and perlite (20% perlite to 80% coco coir). I am growing a variety of chilli in the autopots called Joe's Long. These have been propagated in rockwool blocks. On planting I bury the bottom third of the block in the coco/perlite mix as shown in the picture.
To finish it off i fill the top of the pot with clay pebbles and cover the rockwool block with a block cover. These pebbles on the top of the pot will help to insulate the pot and will stop the top layer of coco/perlite mix getting dried out by evaporation from the sun or grow lights. Once the plants are in i hand water them from the top with Canna's coco A+B at an EC of 1.6 and a pH of 5.8. These plants will get hand fed from the top for the next 2-3 weeks until i'm sure the roots have made their way throughout the entire pot and the plant is ready to be fed through the valve at the bottom. If you start by feeding from the bottom straight away quite often the plants small root system cannot cope with the saturated growing medium and will get off to a slow start. By hand watering every 2-4 days for a few weeks you will get the plant ready quickly for bottom feeding. I have filled the tank with nutrient solution but have kept the tap on the bottom of the reservoir closed, this way i can top feed the plants with a jug out the reservoir when they need it.
Cant wait till I've got some lovely long hot chillies in a about 3 months time. I find chillies and peppers the best plants to grow in Autopots, although I've had good success with melons, and tomatoes too.
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.
