Horticulture, the science and art of cultivating plants, is constantly evolving with innovative techniques and technologies.
One such technology that has gained significant attention in the recent years is the use of suction tubes.
These simple yet effective tools offer numerous advantages and applications in the field of horticulture.
In this article, we will explore how to install and use of suction tubes to the benefit of any horticultural producer.
What are suction tubes??
(Picture courtesy of Mottes Bulletin)
Suction tubes, also known as aspirators are hollow tubes equipped with an opening at one end and a collection at the other. They have a ceramic tip that draws solution from the soil.
Suction tubes are a means by which a soil solution may be drawn from the root zone, which enables the farmer to test some of the nutrients present in the soil, within the rooting zone. Thus with the ability to carefully monitor the soil solution, management decisions with regards to soil fertility may be constantly made.
Objectives
The objective of the suction tube is to measure and quantify certain factors with regards to the soil solution.
Aims
The aims of using a suction tube are as follows:-
i) to be constantly aware of the fertility levels in the soil solution which encompasses the root zone.
ii) to use the information obtained from the soil solution to make decisions on the fertility requirements of the crop.
N.B – Suction tubes work well in crops that are on the ground for a long period of time. Here we are looking at crops like plantation trees ( citrus, bananas, tea, coffee etc. ) greenhouse and tunnel cut flowers etc.
These crops will need regular replenishment of nutrients thus suction tubes play an integral part in deciding what nutrients are enough and which ones needs replacement.
In most cases regular nutrient replacement is through the use of soluble fertilizers that are mixed in tanks. Pumps are used to push the solution through dripper lines that emit the solution directly to the crop. That is why suction tubes are placed at the root zone.
Practical Usage
When installing the suction tube, it is important that the correct place in the field or greenhouse is chosen. Normally they are placed in between the two tensiometers at the depth of a minimum of 30 cm.
(Picture courtesy of Mottes Bulletin)
In order that the soil solution may be drawn into the suction via the ceramic tip, it is necessary to create a vacuum within the tube. This is done with the aid of a syringe as follows:-
STEP 1– Remove the stopper from the rubber tube
2– Insert a syringe tip into the end of the rubber tube.
3– Pull back the syringe plunger,
4– Pinch the rubber tube so as not to allow any air to escape from the tube.
5– Remove and reset the syringe.
6– Repeat this process until there is a strong vacuum in the tube.
7– Whilst pinching the tube, replace the stopper into the end of the tube.
The vacuum in the suction tube should be made fifteen minutes before the irrigation set begins.
Twenty four hours after the irrigation set has been applied, it is then necessary to obtain the solution from the suction tube. Again, this is done with the aid of a syringe as follows:
STEP 1 : Pinch the rubber tube leading from the top of the suction tube.
2 : Remove the stopper from the end of the rubber tube
3 : Insert the syringe end into the rubber tube
4 : Release the pinch.
5 : Pull the syringe plunger out and soil solution should fill the syringe.
N.B. This may need to be repeated several times to obtain enough solution from the suction tube.
After solution has been obtained, release the vacuum from the suction tube.
Some Useful Tips
i) A large syringe is better than a small one
ii) Only leave the vacuum on the suction tube for as long as it is required to obtain a solution i. e . maximum of 24 hours at a time.
iii) The solution should be placed onto a dry, clean container and tested as soon after it has been drawn as possible.
iv) It should only be necessary to draw a solution once or twice per week.
Testing The Solution
Three tests are made on the solution from the suction tube:
i) E.C (Electrical Conductivity)
ii) NO2/NO3 ( Nitrates/ Nitrites )
iii) pH
Digital meters are available for testing both the Electrical Conductivity and pH. Nitrates and Nitrites are tested through the use of a buffer solution and litmus strips ( the pH sometimes is measured in the same way).
Testing should be carried out in both soil solutions and the dripper line solutions on a once weekly basis and the results recorded as per the example below.
The above results shows that after the application of fertilizer solution is applied in quantities of 35m3 or 40m3, the EC and pH rise or drop. This simple mini-lab results can be used by the farmer to increase or decrease the amount of water and fertilizers needed by the plants. Young plants and pruned plants because they do not have a large root system need EC of about 0.8 and big flourishing plants need EC of 1,0 – 1.5.
Care and Maintenance
- When installing, push a sodium hypochlorite and water solution into the tube until it bleeds out of the ceramic tip. Then suck out the solution and install into the ground.
- Carry out the above procedure once a year, or more if necessary, to ensure the ceramic tip does not become blocked. If required clean the outside tip with a soft brush.
Take away
The use of suction tubes in horticulture offers numerous advantages and applications across various aspects of plant care.
From targeted watering to precise fertilizing these tools revolutionize the efficiency and effectiveness of horticultural practices.
The enhanced control, reduced wastage and environmentally friendly friendly approach make suction tubes indispensable tool for professionals in the field.
As horticulture continues to evolve, this technology is likely to play an even more significant role in the years to come.
I really hope that you find these tips useful and that they help you with installation and use of suction tubes.
What has been your experience with the use of drip irrigation systems in horticulture production?
If you have any experience, questions or need further clarification please leave your message in the comment section below and I will get back to you.
Happy gardening!!!!!!!!!!
Here’s a little transparency: Our website contains affiliate links. This means if you click and make a purchase, we may receive a small commission. Don’t worry, there’s no extra cost to you. It’s a simple way you can support our mission to bring you quality content.”
Using suction tubes when growing fruits and flowers can be a very helpful way for farmers and growers to see if the plants need specific nutrients or water. Can suction tubes also be used for growing vegetables, or does it need to be a crop which is perennial, rather than annual?
What is the reason for inserting the suction tubes fifteen minutes before irrigation? Does one always wait 24 hours after irrigation to take the sample for testing, or does it depend on the type of soil? Thank you.
Thank you for your comment.
1) Yes the most common use of tensiometers is when growing flowers and fruits. I would rather have tensiometers on perennial than annual crop. Annual crops have too short a life cycle for effective use of tensiometers. I tried to use them on a mange tout crop and the results were not pleasing.
2) Tensiometers need to settle 15 minutes before irrigation so that when irrigation solution is introduced, the suction then gradually starts collecting the solution. The same applies to drawing solution from suction, it has to be done 15-30 minutes and the solution tested. This is that the grower or farmer can then decides the amount of water and nutrients to add if need be.