Make growing easier with fewer drawbacks
Elevated gutters, is becoming more the “norm” when building new greenhouse structures. It is an important decision to make and comes with extra expense however, this expense can be offset as a traditional internal drainage system is not required when growing from the ground.
There are other floor gutter options available that require a perfectly level floor. If the floor isn’t level you will end up with potential troughs where the water sits. If you decide to slope your floor, to compensate, remember it will potentially create temperature variation.
Gutters offer you a large saving in labour. It is easier to put substrate on and to remove from elevated gutters than the ground which is friendly on the back. It is far easier and efficient when planting. For a period after planting (time varies depending on what vegetable you are growing) it is very easy to perform the initial jobs like clipping/tying up the plants and carrying out important plant maintenance.
Below are some of the benefits:
A, Hygiene: Much easier to clean your floors and disinfect the greenhouse.
1: Gutters are the best option for creating the even surface for the substrate to sit on. This is very important to encourage even distribution and water across the substrate. No brainer.
2: The irrigation is attached to the gutters either underneath or as I have seen in some places on top attached to a grow pipe. I prefer the irrigation lines underneath the gutter with the micro tubes bending up to the slab. I like it that way shade the main irrigation lines and its tidy and one less pipe in the way.
C, Drainage: For capturing runoff and recycling - it is a great system for reducing contact with the ground and extra potential contaminants.
D, layering crops is easy with gutters.
There are many advantages to gutters, some growers like the fact they can drop their leaves underneath the gutters. Others like the fact that there are less hazards in the way to prevent trolleys causing damage.
Types of Gutters:
Once you have decided if you would like to have an elevated gutter system, you then have to decide what is the best system for you. There are internal and external gutters, where the substrate can sit on top of the gutter or inside the gutter. My preference is the external option. Some internal gutters are designed to take the runoff away from deep grooves internally either at the side or in the middle of the gutter. Certain vegetable root systems (like tomatoes and cucumbers) potentially could grow vigorously out of the bags, so you will be in a world of trouble when roots start blocking an internal guttering system. The external or top hat gutters with the collection groove exposed on the outside far reduce the potential for unwanted roots growing out of the bag and into the drain. Top hat elevated gutters make collecting horizontal slab profiles easier also.
There is an option of hanging or ground mounted gutters. Ground mounted are better if there is a lack of strength in your structure. Ground mounted gutters will mean you have stands on the floor and this makes it a bit more difficult when cleaning. When ordering your greenhouse consult with the builders, let them know if you plan to install hanging gutters.
The width of your gutter will depend on your substrate, this should be a consideration if you plan on interplanting. Generally, the standard width of gutters is approximately 200ml wide, but I have seen different sizes around the world.
Height of the elevated gutter from the ground is not standard and this does depend partly on the height of your greenhouse. For older, lower structures that are being retrofitted, I would not be too high off the ground. The top of the crop should be as far away from the vents as possible. This is the reason modern greenhouses are built higher, to create a better environment for the plant. One drawback from gutters is the increased temperature the substrate will achieve sitting higher off the ground. It will possibly be slightly warmer, which is great in winter, but could cause a few challenges in the summer.
New greenhouse structures are designed with ‘truss posts’ See fig 4. It is a great idea to eliminate the gutter sitting too far to one side of the row. It helps create even spacing between gutters and therefore between plants.
This photo demonstrates the immediate impact and benefit that elevated growing gutters has.
Image from Apex Greenhouses. Contact Apex Greenhouses if you are considering building a greenhouse structure with gutters.
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Article Written by Stefan Vogrincic, Consultant, Grower2Grower