Updated: January 30, 2020
Walls O water, Walls Of Water, water teepees, season extenders are all names for small, inexpensive plant protectors that use water as insulation to keep tomatoes or other heat loving plants warm when it’s cold.
These walls of water can help you get the jump on the growing season by as much as a couple of months. With this much of a head start, your plants will get fully established before pests arrive on the scene. This means, you’ll get more and better tomatoes than you ever have before.
I bought my Walls Of Water back in 2010. Amazingly, I’m still using them. In fact, they still work great! How many things did you buy back in 2010 that you are still using today?
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But really, do Walls o Water work?
Cody Witt from the company called WeCycle Consulting is tremendously successful at growing tomatoes. In fact, he gets between 50 and 100 pounds of tomatoes per plant in his garden in Colorado (where it’s cold much of the year).
What’s his secret? Plenty of top grade compost and Walls O Water.
Cody firm helps businesses save money through composting. As you might expect for someone in his role, he’s got a lot of top notch compost available to him. There’s no doubt that compost is a huge factor in growing great tomatoes, but it was the use of Walls O Water that got my attention.
Walls O Water is one of many brands of “water teepees” that are used as mini greenhouses with warm weather vegetable plants like tomato, pepper, cucumber, melon and eggplant. The primary reason why people use them is to transplant vegetable plants outside sooner to get an earlier start to the growing season.
Extending the season
I’ve used a number of methods for extending the season for tomatoes, including low tunnels, hoop houses and cold frames. As a result, I know that if you can start your tomato plants in the ground sooner, you’ll get better yields. This is because the plants grow larger both above the ground and below.
Last year I planted my Brandywine and Caspian Pink tomatoes early using a cold frame. I was amazed how much better these tomatoes did than in years’ past.
The tomatoes were larger and they ripened a little earlier in the summer. Furthermore, the plant stayed healthy and giving well into the fall.
Walls O Water as part of double protected culture
Cold frames, row covers, hoop houses, polytunnels, high tunnels and Walls O Water are all techniques of a plant growing method called protected culture.
You’ve heard of “agriculture” and probably “aquaculture.” Lately, a lot of backyard growers are also talking about “permaculture.”
“Protected culture” is like those. It refers to growing plants using protection from the elements.
During cool nights, the Walls of Water keep the plants warm with water that has absorbed heat during the day.— Suburban Hobby Farmer
I start some of my tomatoes and cucumbers in Walls O Water inside a hoop house. This is an example of DOUBLE protected culture.
Using this double layer, I’ll have to be very careful I don’t fry the plants. I find that newly transplanted plants with immature root systems don’t handle temperature extremes well. I’ve lost some plants in double protected culture because it’s too hot during the day.
But this technique will protect my tomato plants from the cold March nights without having to heat the hoop house. Plus, it will keep the tomatoes cool when the hoop house heats up.
How can Walls of Water keep tomatoes both warm in the cold and cool in the heat?
During the heat of the day the water teepees insulate and cool the plants because the water is still cool from the night before.
During cool nights, the Walls of Water keep the plants warm with water that has absorbed heat during the day.
But this works only to a point. Sometimes, when it’s very warm in the hoop house, it’s best to take the Walls Of Water off during the day. This can be a hassle especially if you have a lot of plants.
Tomatoes a few days sooner
Strangely enough, the consensus is that you don’t get tomatoes much sooner using Walls O Water or even double protected culture. This is probably because the tomatoes can’t set fruit until the night temperatures warm up above 60 degrees F.
Still, Walls O Water do protect against frost, which in my part of the country is a very real possibility into early May. It also allows you to grow much bigger, stronger plants that have better yield.
Here’s a Wall O Water advertising video showing you how they work.
Here are a couple of other alternatives to Wall O Water:
Bosmere Kozy Coats Water Filled Garden Teepee
Dalen Gardener Season Starter Plant Insulator
The most difficult part
Maybe the most difficult part of using a Wall O Water is getting it off without damaging the plant. Cody leaves his WOWs on throughout the growing season. If you live in a warmer climate, you can’t leave them on because the plants will fry.
Getting them off gets even more complicated when you use tomato cages. You have to be careful that the cages don’t puncture the plastic cells.
Extend the Growing Season
All my articles on hoop houses, cold frames, indoor growing, winter sowing and more!
It’s best to put cages on after you remove the WOW.
The other thing to consider is the tomato plant stems are pretty weak after the Wall O Water is taken off, so support is even more necessary than normal.
I use a string trellis method because it works better than cages.
Walls Of Water FAQ
Here are some of my readers most frequently asked questions:
It uses water as insulation to protect tomatoes and other heat loving plants from cold, wind and rain. This gives your tender, young plants a chance to establish themselves before problematic insects arrive on the scene. It also keeps tomato plant leaves dry and out of the rain, preventing disease.
If your seedlings don’t have established root systems that stretch underground outside of the WOW, you’ll have to open up the water teepee and water inside. But this is not the best situation when it comes to tomato plants. They don’t like water on their leaves. So it’s best to plant established seedlings with roots that stretch under the soil, so you can water all around the WOW without getting the leaves wet.
You can remove Walls Of Water when the danger of cold or cold / rainy weather is over. Some gardeners worry that they will fry their plants if they leave them on during hot weather. This is only a danger if it has been consistently hot for several days and your plant’s root system is not well established. Tomatoes can take some heat. Some people in cooler climates never remove WOWs. This protects the base of the plant from water damage.
You can pull the top open and lift straight up. It’s easier with two people, especially if you’re worried about spilling water on your plants or breaking vines. But you can do it easily with one person and it almost always works out fine.
In my experience, color of the WOW does not make a difference. Although, some people truly believe that blue or red is better for the plant than other colors.
I’ve had my WOWs for over 10 years and the plastic hasn’t degraded. However, I have had seams open up so that a cell no longer holds water. Most of mine are still working after all these years.
I have used Walls Of Water inside my hoop house. This is called double protected culture. It will keep your plants warmer, but you have to be careful. Double protected culture can overheat your plants and kill them. This is especially true if your seedlings do not yet have well established root systems.
Wall O Water alternatives include Cozy Coats, Season Starter Plant Insulators and other brands of water teepees. You can also use a cold frame or low tunnel or a klotch if your plants will fit.
If you live in an areas where the spring is cool, I suggest you give walls of water a try. It’s an inexpensive way to give your plants a head start.
Related articles you might enjoy:
- I shopped around for hoop house kits. Here’s what I learned.
- A Hoop House is a Tomato Growing Machine
- How to Grow a Million Cucumbers in a Hoop House
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