Garden season extenders allow northern gardeners to grow crops of warm-weather plants like tomatoes and peppers longer in the fall, grow cool-weather crops through the winter, and start our spring gardens earlier. Plus, your plants will be healthier and should produce more!
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Garden season extenders, in the form of row covers, cloches, cold frames, hoop tunnels, and more, have become an integral part of my garden in the spring and fall.
When I read Steve Solomon's Growing Vegetables West of The Cascades years ago it inspired me to try and lengthen the typical harvest window for our area (PNW zone 8).
I even flirted with the idea of year-around gardening. But only briefly, as I learned this important fact about myself:
Gardening when it's 35 degrees and raining is not fun.
As much as I wish I could enjoy cold-weather gardening, I'd much rather be knitting in front of a fire.
Though if I could have a huge greenhouse attached to my house so I never had to walk outside like Elliot Coleman, then I definitely would have a winter garden!
How to Use Garden Season Extenders to Grow Crops in Cooler Weather
You can use season extenders in the fall and throughout the winter into spring in the following ways:
- Plant cool-weather crops like spinach, lettuce, onions, and peas in the ground as early as possible in spring, covering with floating row covers or plastic hoop tunnels to protect from both heavy rain and light frosts.
- Use a cold frame to help harden off seedlings in spring.
- Place floating row covers on brassicas (broccoli, cabbage, etc.) and tomatoes to protect them from weather and pests, and be able to plant earlier (bonus benefit: the plants grow stronger and bigger!).
- Cover warm-loving peppers with a simple hoop house to get more ripe peppers in cooler summers.
- Plant fall crops, using shade cloth in the summer to protect the seedlings and moving to cloth or plastic covers was the weather changes.
- Experiment with overwintered crops, covering with cloth or plastic row covers and cold frames. (Overwintering is when you plant a variety in the fall that grows slowly all winter and starts producing in early spring- the two I've had the most success with are overwintering cauliflower and purple sprouting broccoli. Here is a group of popular winter vegetable seeds you can try to see what works for you).
Below you'll find different tools to use to extend your harvests, how to use them, and how they've worked for me.
6 Garden Season Extenders To Use
1. Wall-O-Waters/Tomato Covers come in both a green and a red version (the red is supposed to help the fruit ripen faster). Use these to protect tomatoes and peppers in early spring in order to have ripe fruit sooner and a longer harvest season.
How to Use:
- Place a 5-gallon bucket upside down over the seedling and place the empty cover over the bucket.
- Use a hose to start filling each tube in the cover, filling opposite tubes to keep things even.
- When all are filled, remove the bucket carefully and the cover will stand up on its own.
- To keep the center more tightly closed, remove the water at the top of the tubes. Fill to top to keep the top open in warmer weather.
These are a great option for smaller gardens. I used them for years with the six tomatoes I planted in my city garden's 3 'x 6' beds.
You'll see a lot more early growth using these than your neighbors. The year I got closest to the "4th of July Ripe Tomato goal" (I think it was the 10th) was the result of planting in mid-April with Wall-O-Waters.
(Note: to be clear, there are a LOT of people in my area who plant tomatoes out in mid-April without any protection but the tomatoes don't like it and don't grow very well. However, they don't die, so people keep doing it...)
The Drawback to Wall-O-Waters
It takes A LOT of time to fill all those water chambers. Like, a lot.
How much time? When I expanded to 18 tomatoes in my larger rural garden, I started covering the tomatoes like usual but had to call it quits after two hours, frozen hands, and only 10 plants covered.
So I moved onto the following option for tomatoes, which has actually worked better!
2. Floating Row Covers are wonderful for not only extending the harvest, but also to:
- Keep brassica crops (broccoli, cauliflower, & cabbage) from being infested with aphids and cabbage loopers and to give them a healthier start.
- Cover tomatoes in the early spring (this replaced the individual Wall-o-Waters in my garden).
- Protect early sowings of lettuce and spinach and to keep the rain from ruining the late lettuce.
- Protect fall seedlings planted out in July and August (like shade cover with ends open for air).
- And even to protect newly planted seed beds from cats and birds.
How to Use:
Cloth row covers are simple and adaptable to use:
- Rest the row covers directly on top of crops.
- Or use small metal or pvc hoops to hold it over planted rows or raised beds, as seen in the lower photo above. Use simple clothespins to secure the cloth to thin metal hoops or pvc clips with pvc pipe.
- Secure the edges with rocks or garden staples and it will keep the bugs out, too, until the plants outgrow it.
Drawbacks to Cloth Row Covers
If it's windy, they may fly off or tear in places. They do tend to tear after 1-2 seasons anyway, just from use.
But they are inexpensive enough and do the job so simply that I always have some on hand.
3. Cold Frames
Adding cold frames to your garden, whether more permanent like the wooden box pictured on the left or portable like the reasonably-priced fabric option on the right, are really good for a couple things:
- To help harden-off seedlings.
- To be able to start lettuce and greens earlier (in less soggy soil).
- To keep harvesting greens and smaller items well into the fall and maybe even winter.
DIY Cold Frames
If you are up for making them yourselves, this article links to a number of different ways to make DIY cold frames.
A word of caution, though, about making frames with old windows (like we did, which you can see in this garden tour) - they do not last more than a season before the glazing disintegrates and the glass falls out, shattering on it's way down. #liveandlearn
Drawbacks to Cold Frames
They can be expensive and are often permanent structures taking up space in the garden.
For smaller gardens or herb gardens, cloches may be a good way to protect a few plants and look good doing it.
In addition to the standard jar shape, they come in a rectangular version with individual air vents to help regulate the temperature, so in some gardens, these may be the way to go.
The plastic is heavy enough that they could be used over and over again.
Drawbacks to Cloches
Obviously, they only cover one to a few plants, so they are not very practical for larger gardens.
They could fly away in heavy winds and are often expensive.
5. Milk Jug Garden Covers
Using milk jugs with the bottoms cut off as cloches (and more) is a a really great way to use what you have and save in the garden.
There are people in colder gardening zones who are able to start seedlings outside even in frost and snow using milk jug greenhouses!
I haven't used these for more than simple cloches over a plant here or there, but you can see more ways to use milk jugs in the garden here.
Drawbacks to Milk Jugs
Hmmm, maybe not the prettiest thing for the garden? Also if you don't drink milk you'll have to scrounge some up.
6. DIY Hoop House (or Tunnel)
Using a simple pvc hoop house with either row cloth like pictured above, or plastic like below is the ONLY way I can get fully ripe, red sweet peppers in our mild summer climate.
How to Make & Use A PVC Hoop House
It's easiest to use these with raised beds, since you then have a defined edge.
- Purchase 1/2-inch PVC pipe to fit your bed at the height you want, with at least 6 inches below ground.
- Attach metal 1/2-inch "U" brackets to the inside or outside of a raised beds - two on each side (one above the other) will hold the pipe best.
- Place one side of the pipe into the brackets, bend the pipe to the other side and fit into the brackets. Repeat with remaining pipe.
- Plant the bed before adding the cover.
- Cover with your choice of row cover or plastic, attaching to the pipe with pvc clips. (I used to use a perforated plastic cover so you didn't have to open and close the ends when it's warming up, but I can't find it anymore. Maybe use clear plastic and add some slits for air flow?)
Add the cover when you plant, keeping all the edges closed with clothespins or metal clamps. Rocks at he corners and edges help to keep the cloth to the ground.
As it warms, open the ends to let air flow through and pollination happen.
Close the ends if your weather turns cold to extend the harvest into fall if appropriate.
Drawbacks to Hoop Houses
Harvesting is more difficult, but you could try making this DIY hoop house for raised beds that is hinged for easier access - I hope to try it one day!
And maybe the whole DIY thing is maybe not for you.
Do you use garden season extenders or have any plans to? I'd love to know how they work for you!
This article about garden season extenders has been updated - it was originally published April of 2015.
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