Frequently Asked Questions
General
What is a Windowfarm?
A Windowfarm is a vertical, hydroponic farming system for year-round, indoor growing in your windows. It’s not really a "growing machine," as it still requires the conscious intervention of a farmer-- you! A Windowfarm does make it easier for you to get started growing hydroponically even in limited space and during fall, winter, and spring months.
How does a Windowfarm work?
A pump on a timer periodically circulates the liquid nutrients through each column of plants in a closed loop. Water is moved from the bottom reservoir to the top plant bottle via an “air-lift” system powered by an aquarium air pump. Water trickles down from bottle to bottle, through the plants' hairy root networks, and any unabsorbed nutrient solution is collected again as it trickles into the bottom reservoir bottle.
A nutrient solution, which varies by kit, is used to 'feed' the plants. See our nutrient and supplement list to learn more about nutrients.
What are the goals behind the Windowfarms project?
Checkout the Story page.
What can you grow in a Windowfarm?
You can grow almost anything in a Windowfarm, as long as it is not a root vegetable (like carrots, radishes, and parsnips). Some of our favorites are the following:
Arugula, Basil, Calendula, Chamomile, Cilantro, Collards, Cress, Dianthus, Dill, Kale, Lemon Balm, Lettuces, Lollo Rossa, Marigolds, Mesculan, Mint, Mustard, Nasturtiums, Pansy, Parsley, Safflower, Sage, Salvia, Snapdragons, Snow Peas, Sorrel, Squash, Stevia, Sugar Pea, Swiss Chard, Thyme, Tomatoe, Violas.
Hydroponics
Hydroponics? What does that mean?
Hydroponics is a technique for growing plants without soil. It is up to 10x as efficient in its use of space and the productivity of the plants increases dramatically.
Nutrients the plants need are dissolved into water and plants' roots are bathed in the solution at regular intervals. Plants grown hydroponically are rooted in a special growing medium that allows the right amount of air, water, and nutrients to pass by the roots. In the Windowfarm system, the growing medium is made of clay pellets, which are completely inert. This means they won’t leech out any toxins into your plants. The pellets are there to support the plant since it doesn’t have any soil to anchor itself to.
What are the benefits of hydroponics?
A hydroponic system is efficient an efficient way of delivering nutrients, water, and air to the roots of the plant. This has three benefits:
- The roots don't need as much space to spread-out. Instead of growing far and wide, the root network of a hydroponically-grown plant is dense and compact.
- A larger plant can be grown with a smaller pot size than soil-based conditions.
- The growth rate of a hydroponic plant is higher than the rate of the same plant in soil.
The Windowfarm system is compact, modular and vertically oriented, making it appropriate for urban spaces which lack lots of horizontal space.
Kits - General
What kind of Windowfarm kit is right for me/us?
Are you doing this at home? Then a Home Kit is right for you.
For individuals who would like to add some green space to their home we suggest choosing between our 2-column or 4-column kits. Home kits use smaller reservoirs as collection receptacles for the base of your farm. To allow for the variation that we find across windows, we include extra plant bottles in case your window is outside our standard expectation. We also provide you with slightly different nutrients and a log book for recording your findings and tracking your plants.
Are you an Institution or School? You’ll want to use a School or Research Kit.
If you are part of an institution, we highly recommend that you get a school kit. Installing and maintaining a Classic home system in an institutional setting will be much more labor intensive down the line. Our support materials and community are designed for institutional use of school kits. Home kit use in institutions is not supported. The reservoir for a school kit is bigger than our home kits which allows you to have longer periods of time between water refilling. The pumping and tubing system is also more robust to accommodate the issues that can arise when multiple people participate in a hands-on project.
Are you a business, exhibition or event? Contact us for Custom Installation services
If you’re a business hoping to install an elegant windowfarm in your storefront to use for marketing purposes or for use in an exhibition, we recommend that you use our contact page to inquire about consulting, commissioning a custom build, and/or contracting maintenance services. We can help you understand what will be needed to support a windowfarm under your specific conditions and what you’ll need to ensure you’re getting the best performance from your system. Use of school kits in businesses, exhibitions, and events is not supported.
How much noise does a Windowfarm make?
Each Windowfarm is powered by a single aqarium air pump, the same one that is used to aerate fish tanks. Generally, there is a slight hum to the pump and a trickling fountain-like drip and 'gurgle' sound produced by the water's movement. Most people report that the sound is soothing and not distracting.
Will a Windowfarm fit in my window?
Checkout the Kit Sizing page.
Kits - Purchasing and Pricing
I am buying for a school and they require all vendors to be on a list. Can you fill out a form for me?
Please download this PDF which contains all needed information. It includes Name, Business Name, EIN, Tax ID, Federal ID, NYC DOE Vendor ID, Phone Number, Email address. Also includes a Sole Source Letter.
I want to pay by Check or Money Order. How do I do that?
Please download and print this PDF. It contains directions on how to mail-in payments.
I work with a non-profit organization. Can you offer me a discounted price in a Windowfarms product?
Unfortunately we cannot give discounts on our kits as we are working towards our own mission.
We only charge sales tax to customers within New York State. We do consider requests for sales tax exemption for NY-State non-profits with sales tax exemption status. Please submit your paper work, order details, contact person, and shipping address using our contact form.
However, part of our mission is to make the instructions on how to build one freely available to anyone so that cost is not a barrier. You can access those instructions at http://our.windowfarms.org/tag/officialhow-tos
Kits seem expensive. Why do they cost so much?
In comparison to other hydroponic kits, we offer a platform for growing many more plants for significantly less money. We find that sometimes people perceive a lower value because we house the systems in recycled water bottles, whereas the cost of recycling is much greater than the cost of causing new landfill-bound materials. People also compare our kits to growing in soil. If you have access to a sufficient amount of soil and conditions to grow food that way, we definitely recommend you stick with soil. We have worked hard to get our kits as close as possible to the price of ordering all the parts at retail prices from various different sources. Our team is able to fund the project on a slim margin between the wholesale prices we get for buying in bulk and the cost of your ordering all of these parts at retail from various different sources. Thus, after some research, you will find that our prices are reasonable and, in general, tend to be less expensive than making one yourself.
Kits - Shipping
How long does it take to receive a purchase?
Please read our Store Policies page.
Do you ship kits internationally?
Yes! Please go here.
We provide free How-Tos for this purpose. Go to http://our.windowfarms.org and signup to our online community to gain access to our How-To instructions.
Kits - Components
What comes in a kit? How do they compare?
Visit the Home Kits Page or Education Kits Page, and click on the link that says "Kit Details and Comparison". Everything in the kit is listed there in very specific detail.
Is the pump supplied in the kit?
Yes. A pump is included in every kit. Visit the Home Kits Page or Education Kits Page, and click on the link that says "Kit Details and Comparison". Everything in the kit is listed there in very specific detail.
What is the electrical cost of running the pump?
The cost of electricity to run a Windowfarm will cost you a few dollars per year.
All Windowfarm systems come with a timer, which we recommend setting at equal 15 minute on/off intervals throughout the day and night. This means the pump is running 1/2 time, in other words 4383 hours in one year. Using an average energy cost for US Residences of $0.12 per kWh (kilowatt hour), here's the breakdown:
Is "fertilizer" or nutrient solution supplied in the kit?
Yes. Hydroponic growing fundamentally requires a nutrient solution in the water. Approximately 6 months of nutrient supply is included in every kit. Visit the Home Kits Page or Education Kits Page, and click on the link that says "Kit Details and Comparison". Everything in the kit is listed there in very specific detail.
We now ship all of our kits with hydroponic nutrients labeled "premium, natural and organic-based plant food." The ingredients in these nutrients are listed as the following: fish meal, composted seabird guano, kelp, rock phosphate, potassium carbonate, magnesium cabonate, & calcium carbonate.
What type of bottles are used in the kit?
In North America, the 1.5L water bottles produced by Nestle Waters® uniquely accomodate the 3" diameter hydroponic netcups included with the kit. Nestle Waters® sells the following brands of water: Poland Springs, Deer Park, Calistoga, Arrowhead, Ozarka, Zephyrhills.
We sell both prepared and un-prepared bottles for the kits in our online store. We offer kits for sale without bottles, so you can use a variety of other containers: metal martini shakers, gourds, or make your own.
Kits - Sizing
What do I do if my window is smaller or larger than a standard 4' x 6' window?
Windowfarms are modular, allowing flexible size modification to fit into almost any window. In general, one bottle is about one foot tall, so 5 bottles will fit into a standard 6' window. The kits give you supplies for 5' tall columns, leaving some room at the top and bottom for your tubes and pump.
You can always subtract bottles from a column to make it shorter. Just cut the rigid tube you get in your kit to the proper length. You can cut it with a handsaw or score it with a box cutter and then snap it off to length.
You can add bottles on top to make your columns taller by adding more rigid tubing and suspension line. However, at some point, your pump will not be able to pump high enough.
Kits - Setup
What do I do once I receive my kit in the mail?
Checkout the Kit Guides page for all the info you need to get your particular kit up and running. Select your kit type and it will take you to our setup guides which are only available in a click through format. If you want to have printed instructions, just click through each page and print them individually.
Why don't you include printed assembly instructions in the kits?
We made a conscious decision not to include printed instructions in the kit and not to send paper instructions by mail. We want the kit to be a social gardening experience, where windowfarmers connect with one another online for support. If you have a problem setting up your kit, and you are following online instructions, you are more likely to say something on our site and we can help. We want that community experience to continue in the long term beyond just the setup.
If we wanted to move the system to a different room at the end of the year, would this be difficult?
If the two rooms' windows are very similar, no. Doing so would probably take two people about 30-45 minutes to gingerly move the plants and you would need to re-install the suspension hardware in the new room. We cart our display systems around all the time. However, if the new room's windows are a totally different height, you may need to alter the mounting by adding in a bead chain extension or by removing bottles and links from the bead chain.
Can I use a Windowfarm outside?
Sure, but Windowfarms, like other hydroponic systems, are designed for a controlled indoor environment. If your windowfarm is exposed to rainwater, it may upset the balance of the nurients in your reservoir. Strong winds can also damage the structure or swing your plants around. If you have access to good, healthy soil, windowfarms really might not be the best plan. Why not grow with the dirt you've got?
Will I need to supplement my Windowfarm with artificial light?
Your plants should get at least 8 hours of light per day, and as much of possible of that light should be natural light. If you have a window with poor direct light (especially a northern-facing window in the northern hemisphere), and/or if your plants appear to be 'leggy' (long stems with few leaves), it means you will likely need to supplement natural light with artificial light.
What lights will work?
The latest generation of Compact Fluorescent Light Bulbs (CFL) in the Daylight Spectrum (above 5500K) are inexpensive ways to add artificial light. These can be purchased at a local hardware store and inserted into a standard lamp socket, for example a clip lamp with its shade removed. The lights should be positioned as close to the plants as possible while avoiding contact with the plant. Two or Three bulbs positioned between each column is appropriate but will take experimentation. See this photo for an example setup.
Kits - Troubleshooting Waterflow
Help! My water isn't running!
Access the Kit Guides page for thorough troubleshooting tips to get your water flowing. If you are still having trouble, hike over to the community site and click on the airlift and troubleshooting tags to read about solutions other folks have developed. This is what the site is great for!
Kits - Maintenance
How much algae and 'dirtiness' will accumulate in a Windowfarm?
There will always be some buildup of algae. It simply needs to be cleaned every couple of months. Any nutrient rich medium that is exposed to light will grow algae over time. There is nothing harmful about the algae. The systems are not self cleaning. It is important not to think about the systems as machines. Rather they are platforms for human interaction that allow food growing indoors. There are other hydroponic systems available on the market that make claims to eliminate algae growth. That is not currently a large concern in our community so we are not taking on the cost of addressing it.
What type of maintenance does a Windowfarm Kit need?
Checkout the Maintenance and Feeding Schedule page.
What do I do if the heating is turned off in my building at night during the winter?
Hydroponic growing allows plants to grow under unusual conditions-- including extreme changes in temperature-- because you can help control their environment. Institutions frequently cut costs by turning off climate controls during times when no one is in the buidling. Fortunately, as long as the plants' root systems are kept at a consistent and idea temperature, the top part of the plant often can survive through some pretty big temperature drops. So, you need to heat the nutrient solution as the temperature drops. You can put a germinating heating pad under the reservoir and set it on a timer to coincide with the time the heat is turned off. The school and research kits work best in these circumstances because they are less succeptible to problems with temperature control.
How long is it going to take me to get good at Windowfarming?
3 full crop cycles
Human Factors
Noise
Windowfarms make noise when the pump turns on, up to every 15 minutes. Most people like it. There is the general sound of trickling water and the pumps make a quiet hum. Noise of a school kit is similar to an aquarium with a murmur of a pump and periodic gurgling noise as bubbles aerate the water in the bottom reservoir. Home kits are a bit quieter and the pump sound is sometimes amplified by enclosed areas like bay windows. Fiddle with pump positioning and consider making Ian's silencer if the noise bothers you.
Cats
Kitties do love windowfarms, especially if you grow catnip in them. Just like your grandpa tries to squirrel-proof the bird feeder, you can cat-proof your windowfarm. There's a whole branch of the community is working on making them kitty-proof. Join the challenge!
Brown Thumb
"I have a brown thumb; I kill everything up to and including cacti. Am I going to kill my windowfarm too?" There's no such thing as a green thumb and there's nothing magic about growing. It just takes practice, patience, and experimentation with your conditions. Windowfarms are definitely not machines that are going to grow for you. They are designed to make you a farmer. Every farmer loses some crops and the more you learn from failures, the better a farmer you become. So quit second-guessing yourself, get to planting, and join the community for support from tons of other folks both new to farming and experienced!
Taste
"How do taste and nutrition compare?" Hydroponic produce can taste even better and be more nutritious. It's all about the nutrients, which come in all different varieties from horrible chemical formulas used by big ag to rich organic compost homebrews. With hydroponic methods it's much easier for you to select a variety and experiment with your plants' nutrient stream because you're not stuck with whatever is under foot.
Smell
"Do windowfarms smell bad?" Heck no! They smell great! Well, it depends on what you've planted. If you chock it full of garlic chives and durian, your new girlfriend might take issue. So grow stevia and mint and make her a mojito in your fresh-scented bachelor pad!
Bugs
"Do windowfarms attract bugs?" Sure, they attract all the same bugs as a pot of ivy in a windowsill. They are subject to aphids, spidermites, and fungi just like any other garden. As the farmer, your job is to figure out how to control these natural garden pests. Thankfully, you've got thousands of folks ready to help you troubleshoot on the community site.
Advanced Sciences
What if I want to grow big plants?
That's fine. You can grow some pretty big plants, especially large vining varieties like scallop squash or cucumbers, however, you will need to trellis your system. Try to avoid varieties that have tall stalks. Read the back of your seed packet and consult the community site to discuss your plan with more experienced windowfarmers.
Is there a possibility of BPA or other chemicals leaching from plastic water bottles into plants?
Yes, there is a possibility of any container leaching into its contents. There is discussion of this on the http://our.windowfarms.org site. Some scientists in the community are unconcerned, postulating that the size and complexity of the BPA molecule size and complexity is likely too much for plants root hairs to uptake. To be safe, the community and core team are developing alternatives to the use of plastic water bottles and exploring the possibility of incorporating bioplastics into future kits. We are also looking for science-minded volunteers with the appropriate equipment to take-on the challenge of measuring any chemical leaching to verify these concerns.
I've heard about aquaponics... can I incorporate aquaponics into a Windowfarm?
Aquaponics combines fish and plants to create a self-sustainable and self-feeding system. While this is possible to accomplish with a Windowfarm with techniques as simple as submerging bottom bottles in an aquaponic fish tank setup, opting for aquaponics over familiar hydroponic nutrients is not recommended for beginners given the high rate of failure and death of both plants and fish in setting up the system. We encourage new windowfarmers to take on experimental techniques one at a time, rather than trying to do several new things at once. We want you to be motivated in the long term by some early success! There is an environmental danger that we will collectively end up creating a lot of landfill if burnout rates in new users are too high.