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7 Reasons Nursery Growers Should Be Growing In Gutter Connected Poly Greenhouses

Many nursery growers grow and overwinter strictly in ground to ground hoop houses, but some progressive nursery growers over the last several years have been looking more and more to gutter connected poly greenhouses.  Here are 7 reasons you may want to consider a gutter connected greenhouse for your next nursery expansion.

#1.  It is easier to maintain desired temperatures in a gutter connect greenhouse compared to a ground to ground structure.

As growers we are always trying to keep the temperature in our greenhouses where we would like it. I found that growing in a properly equipped gutter connect gave me better control over the temperatures with less fluctuation. With roof vents and automated side walls it is amazing to see how fast you can reach the outdoor temperature, or your desired temperatures when cooling. On the other hand we all hate those dreaded cold nights when we have to start heating. Heating and keeping that desired temperature is much more feasible with a gutter connected poly greenhouse. The high gutters and high roof arches mean the volume of air in a gutter connected greenhouse is much greater. And the larger air volume keeps indoor temperatures from dropping quickly as outdoor temperatures cool down. This means that you will have better control over your heating. It is imperative that we have and are able to have better control over our cooling and heating needs in the greenhouse if you want to grow a consistent quality crop.

#2. Added flexibility for multiple crops in gutter connected poly greenhouses.

We all love to get multiple uses out of a single structure. With a gutter connected greenhouse you can grow one big crop under the whole range, or you can grow multiple crops with dividing walls all under the same roof. My experience with this was growing 3 different crops under one roof with dividing walls. We split the range into 3 sections and had gutter to floor dividing walls between the zones. We also had 3 separate zones on our environmental control computer. With this environmental control system we set heating and cooling all at different desired temperatures for the 3 separate zones. Then at certain times of the year we rolled up all the dividing walls up and grew as one large zone. I utilized the structure for 12 months of the year for multiple cycles of crops, so having rollup sides dividing walls was ideal. Some years we never needed the dividing walls but some years we would have 4 or 5 different crops under one roof. This added flexibility allowed us to be very responsive to customer demands and changes in the market place.

#3. Gutter connected greenhouses for better productivity and lower labour costs than hoop houses.

I always found that working in a gutter connected poly greenhouse was such a nicer and fresher environment. When people are happy they tend to work a lot better. In a gutter connect greenhouse you have everyone under one roof and not scattered over a bunch of coldframes or freestanding structures. This means less time wasted on going from house to house. It also means you can keep a closer eye on your employees if everyone is under one greenhouse. And in addition to productivity while managing a large crew in the winter you are not always opening and closing doors, letting all that expensive valuable heat escape.

#4. Much better for air movement.

In a gutter connected poly greenhouse you always have the option of roof vents and roll up sides. On a 14 foot to under gutter gutter connect you can put a side wall on that opens 10-11 feet high. This gives you a lot more air mass rushing through the gutter connect when cooling. Every GGS gutter connect also comes with the option of roof vents. They are usually raised gutter vents or gutter vents. The roof vents give you the option when the house is getting to warm to let that warm air escape. While opening the sides is good opening the roof is even better for the hot air to escape. It's a fact: hot air rises. So with a roof vent the hot air goes straight out the top. With a roof vent on a gutter connect and the house placed in the right direction the hot air is pulled out with the wind moving across the tops of the roof. It is like a suction for the hot air being pulled out of the roof vent. I found the best option in spring was to have the sides open and roof venting as well. It gave you the best of both worlds. The hot air would rise and go out the roof vent and the cool air from outside would flood through the sides. Most plants need and like good air flow; it helps prevent mildew and foliar diseases.

#5. User friendly gutter connected poly greenhouses.

Gutter connected greenhouses with tall straight sides and webbed trusses make it easy to install shade systems and overhead irrigation systems. The straight lines of a gutter connect allow for installation in a way that gives you complete coverage with ease.  With opening sides ideally we would drop down the irrigation downspouts to just below the height of a fully opened side wall. This way your water isn’t splashing off sidewalls and making its way onto the plants. It is imperative we water our plants properly, and growing in gutter connected greenhouses makes it much easier. Also in a gutter connected greenhouse the trusses and all the overhead equipment can easily be installed high enough out of the way of your workers.

#6. Gutter connected greenhouses maximize production land use.

When you build multiple ground to ground structures, whether Freestanding, or Coldframe you need to leave space between the hoop houses for snow removal, putting the poly on, operating rollup sides, etc.  But in a gutter connected greenhouse range all the land space can be used for crop production.

#7. Gutter connected greenhouses make it easy for a grower to expand crop production.

Adding on to the side of a gutter connected greenhouse is very simple and cost effective.  Most sidewall material can be moved to the new side once the expansion is completed.  Expanding the electrical for computer controls, vent motors and lights is also much easier within a single gutter connected range than it is to bring power to a new freestanding greenhouse. Irrigation systems, heating systems, shading, and other automated controls for growing can generally be expanded easily as you add new bays to your gutter connect range.

Aaron Bonas joined GGS in 2015, prior to that he was the head grower for the Ontario farm at Pan American Nursery Products. Aaron was responsible for the health and wellbeing of over 5 acres of plants and oversaw the pruning and spacing crews. As the head grower he co-managed the nursery to start the clean plants program and was one of the first nurseries to get certified in Ontario. Aaron Bonas is a valuable member of the GGS Sales and Customer Service team.

Supplemental Lighting Considerations for a Commercial Greenhouse

Maximizing lighting efficiency is a major concern for many growers who rely on supplemental lighting in their greenhouse. Here are some criteria to take into account when choosing and maintaining your lamps. The lighting you choose depends on many things like what developmental stage your plants will be grown to, whether the plants receive light from other radiation sources, and the photoperiod length per day for your plant.

Choosing the Right Spectrum for your Needs

When choosing a lighting system, specific requirements may be imposed on the light spectrum by the type of plant being grown, the stages to which it will be grown, plus any additional needs of the grower (e.g. desire for a shorter plant height). All plants require PAR light (Photosynthetically Active Radiation), and this type of radiation is within the 400 to 700nm wavelength range. 

Light Level Requirements
The light level target required for any particular plant can be determined from known light requirements based on scientific studies (e.g. full sun, partial sun, shade, etc). Supplemental light levels need to be only a fraction of complete light levels, while photoperiodic light levels can be even lower. Greenhouse systems companies such as GGS Structures have advanced tools that can precisely measure the natural light levels in your greenhouse, as well as the light levels produced by your supplemental lighting.

Our Sales Manager Michael adjusting the light controls.

Checking the Shadow Area of the Fixture

As with any hanging object in your greenhouse, a light fixture will cast a shadow. You need to ensure that natural light is not being blocked in critical areas of your benches – an issue which your lighting designer should consider when planning the layout.

What is the Efficiency of the Fixture?

Energy costs are the number one expense in a greenhouse. Lighting can take take up a significant portion of these costs. As with any energy upgrade cost, you need to weigh the initial upfront investment against the potential payback. Most greenhouse systems companies can calculate this payback for you, and inform you of how many years it will take to recover your costs. LED lights require a larger upfront investment but use substantially less energy than HPS lights.

What are the Electricity Requirements?

An often overlooked expense is whether or not your greenhouse has the electrical configuration needed to power your supplemental lighting. Your wiring, breaker boxes, and amps of service are all factors that should be considered.

Are there any Rebates Available?

Energy rebates are always something to look for when installing new supplemental lighting. You may qualify for rebates from your local utility, or for efficient energy upgrade programs provided by the USDA or other organizations. 

With all the considerations above, GGS can help you choose the right lighting equipment to fully optimize the growth of your plants. We have partnered with lighting supplier Illumitex to provide growers with industry-leading lighting products.

Dutch Bloemencorso Parade - Amazing Displays Created Using Dahlias

The Dutch Bloemencorso Parade will be held on Septembe 13th, 2015. Every float is made from daliahs to create breathtaking displays. The flower parade has become the oldest and most celebrated ode to blooms in Europe since it first began in 1939.


This annual event sees the town's 20 districts compete to produce the best floral float. The floats are made of wire, cardboard and papier-mâché and entirely covered in thousands of dahlias grown specifically for the parade. A staggering six to eight million dahlia flowers are used to produce the floats. 


The parade is held on the first Sunday of September, and construction of the floats begins in May or June. However, to ensure that the floats are bright and colourful, the flowers can only be applied onto the floats in the last three days before the parade. Hundreds of volunteers work around the clock, pinning the dahlias onto the floats. A jury chooses the best float and elects a winning district.


Source:  |  Pictures: Features


Top Energy Saving Tips for Your Commercial Greenhouse

How many greenhouse operations are concerned with energy savings? I will bet almost every one of them at one time or another! Energy costs are at the top of the grower’s expenses and yet there are many operations that do not spend enough time investigating how to lower their energy use.

Energy consumption is unfortunately unavoidable in a greenhouse environment and complacency often settles in with the day-to-day operations. Occasionally walking through your operation with energy savings in mind is a great way to avoid this complacency and helps to save money daily. Every small bit of energy saved leads to an increase in your margins. Bring a general checklist along and you will be pleased with the energy saving opportunities that will present themselves. Here are some energy savings ideas both in greenhouse structure and mechanicals that can guide you with your checklist:

Structural Checks

When performing annual inspections, check that all areas of the greenhouse structure that can allow air leaks are properly sealed.

  • Check where the structure meets the ground; is this sealed?
  • Are all outside accessing doors sealed when closed?
  • Are exhaust fans properly insulated during cool periods?
  • Are all vents and louvers properly sealed when closed?

Considerations When Building or Retrofitting

Utilize structure designs that maximize the free energy generated by the sunlight – Curved Glass provides the most roof light with large panes of glass curved to the shape of the Gothic Arch, and higher gutter heights 18 to 24 ft not only increases light penetration from sidewalls but helps to disperse shade from greenhouses structural roofs.

Design your greenhouse so that growing zones can be isolated

  • Propagation zones can require more heat than others, tremendous energy can be saved by isolating these high energy requiring zones
  • If zone isolation has not been incorporated, can it be changed? Can heat retention walls and/or curtains be installed?

Use of natural ventilation compared to forced air ventilation

  • Forced air ventilation has a cost, as it uses valuable electrical energy

Pick a structure design to maximize natural ventilation as to not depend on a forced ventilation system. As air passes over the top of a GGS gothic shaped arch for example, with the roof vent open, the air speed will actually increase and help pull your hot air out of the greenhouse. Combine this with an intake like a side vent or rollup side on the windward side of your greenhouse and the ventilation will be even better. This will push your hot air up and let the chimney effect at the top do its thing. The result is a greenhouse approaching actual outside temperatures.

Shading and blackout systems

  • Is there a shading system in place? If not, consider the savings that a shading system can provide during the cooler months. Energy savings can be up to 75%.
  • If a shading system exists, is it enough? Consider a double shading system, even more of an energy saver
  • Is the material thin or shredding? The system is not keeping the cold air out or the warm air in during cooler periods if there are signs of obvious wear. Have a look at replacing the material
  • Does the system close completely? If there are gaps when the shading is closed, that is energy lost


Check your heating system for inefficiencies

  • Is your heating system hot water? If not, consider changing over. A high efficiency condensing boiler can run up to 95% efficient
  • Have your existing boilers or unit heaters had regular servicing and adjusting? A boiler in need of adjustment could be using a lot of energy unnecessarily.
  • Is your boiler room unnecessarily warm? Check to make sure all of your main heating pipes in your boiler room are insulated. If they are not you are again wasting energy.
  • Are there leaks in your heating system? Check around pumps, hoses and connections. A hot water leak is an energy leak.
  • Do you check boiler temperature controls in your climate control system? Bring boiler temperatures down in the warmer months and ensure that boilers are not cycling in the cooler months; energy is used every time a boiler turns off and starts up. This can be limited by looking at longer periods at low fire.

Light and Climate control checks

  • Have light reflective materials been used inside the greenhouse? Ground covers, walls, posts and heating pipes should all be coated in a light-coloured material to help reflect valuable sunlight. If light is reflected rather than absorbed in the greenhouse, the growing zone will have consistent light with little shadow. This valuable sunlight will also help heat the greenhouse quicker, saving energy in the cooler months. Niagrow Systems has its own brand of paint just for these purposes, and it can be applied on all steel surfaces providing a nice sun-reflecting finish. Ask your local Niagrow sales rep for more information on our special Niagrey paint.
  • Have you adjusted your climate controls to account for external seasonal changes? Day length and temperatures radically change with the seasons; adjusting shading, heating, lighting and venting settings can avoid drastic energy waste and take advantage of natural energy in the spring and summer months.

Every greenhouse is unique and may have other issues that are not mentioned on this list. Customizing a list for your operation and following through with energy efficient improvements is the key to a better margin. Keep your list handy when you’re thinking of retrofitting or adding on and you will always do what makes energy sense for your operation.

Planning Considerations Before A Greenhouse Expansion

If you could go back and re-design your existing greenhouse, how many changes would you make? How many of those changes would be minor ones and how many would involve major structural, heating or other mechanical changes? Avoiding this in your future expansion is easy; have a checklist of things you should have in your greenhouse now and incorporate them into the next build.

Things to consider before you begin:


One major complaint that growers have in their existing operation is that they don’t have flexibility to adapt to the needs of a change in crop choice. If your greenhouse is designed for a cool crop with no need for blackout, and by necessity you need to accommodate a day-length sensitive, warmer crop, you are forced to make expensive changes, or to avoid drastic internal climactic changes that a crop can demand. What you have essentially done is to narrow the list of the crops that can be grown in your chosen environment.


Investment decisions that focus only on the past and the present rarely yield staggering returns. Remember this is a greenhouse built to last for decades, so what you want it to do 10 or 20 years from now is almost as important as what you need it to do in the next 5 years. With the changing economy and everything else that has happened in this industry in the last decade, who knows what choices need to be made in the future, don’t let your growing environment limit them!


It seems very obvious but knowing your budget and looking at cost effective ways to at achieving what you need in return from your greenhouse can save you more money in the long run. More than if you didn’t plan and carefully think through your options first. It is worth considering that to accommodate varying climactic conditions involves larger capital, but the expenses are far less to incorporate flexibility into a new build than to an existing structure.

Have a look at the ROI possibilities and this may ease your decision making process! Here’s a quick list of questions that you need to ask yourself before your next expansion:


  • What kind of structure will best accommodate my present needs and provide the flexibility that I may need in the future?
  • What light levels will be best for the types of greenhouse crops I can grow?
  • What range of air flow and ventilation will different crops grow best in?
  • Would dividing the structure into individual zones add the necessary flexibility? Would these zones need their own separate heat controls?
  • Would shading and or blackout meet any present or future needs?

Heating and Lighting

  • What maximum temperatures would I need to maintain to be flexible enough to keep my options open to other crops? Take a look at options like crop heat, rail heat, and under bench heat; would any or all of these be necessary now or in the near future?
  • If supplementary lighting isn’t presently required, does it make sense for the future? This could be determined by looking at research into shrinking growing times for specific crops, and whether the install makes financial sense.

Growing Systems & Irrigation

  • What type of growing systems would make the most sense for the future? Will we be growing on the floor, on benches, containers, or hydroponically?
  • Will you need a hanging basket system? The decisions on your growing systems are crucial as they influence so many other systems such as heat and irrigation.
  • Your irrigation system should allow for future installations and should consider automated controls.
  • You need to consider the following possibilities: Do you need to hand water, overhead watering, an irrigation boom, drip lines, hydroponics or would a flood floor make more sense?


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