Poor Man’s Greenhouse – A Guide to Winter Seed Sowing

Approx Reading Time: 8 minutes

Extending the harvest is critical when you are depending on what you can produce in your survival garden to feed your family. A greenhouse is a fantastic way to get a jump on growing your annual vegetable crops. However, due to space or financial restraints, a greenhouse may not always be an option.

What is winter sowing?  Winter seed sowing is a method of planting seeds in transparent containers in late winter or early spring to get a head start producing your garden bounty. The containers are modified to provide adequate drainage and are filled with soil and planted. The tiny planted greenhouses are placed in a sunny location and hearty seedlings grow even in cold temperatures.

In this post, I am going to introduce you to an effective way to get an early start on your seedlings by repurposing used plastic containers such as milk cartons, soda bottles, and juice bottles. I like to call it the poor man’s greenhouse because it doesn’t require growing lights, heated space, or expensive greenhouse building supplies.

Winter seed sowing is practically free and requires very little labor to be successful. It is my favorite way to start my seedlings every year.

Winter Sowing Does Not Require Electricity or Natural Gas

Growing a survival garden may require you to produce a crop without electricity. Producing seedlings using traditional lights and heating in a greenhouse may not be possible in a grid down event when your food supplies are the most precious.

Winter seed sowing uses a completely passive method to extend the harvest and produce seedlings way before they would have grown on their own. They don’t need to take up valuable space inside of your home to grow well.

Winter Sowing Produces Healthy Robust Seedlings

The seeds know when it is time for them to sprout. You may have to wait a little longer than anticipated to see them emerge or they may take off right away using the winter sowing method. Rest assured that they will sprout when the time is right.

I am amazed at the robust healthy seedlings that are produced using this technique. When I raise seedlings using traditional methods they can be leggy and look a bit fragile. Not so with winter-sown seedlings. They are healthy and robust.

You don’t have to worry about birds or pests devouring your tiny little plants. They are well protected by their little plastic greenhouse.

Winter Sown Seedlings Do Not Need to Be Hardened Off

Seedlings are already acclimated to outdoor conditions and can be planted when the temperature is right. They tend to have significantly less transplant shock than seedlings from a nursery.

Winter Sowing Uses Fewer Seeds

Seeds cost money and may be highly valuable when trying to grow a survival garden. Winter sowing allows seeds to be planted in ideal conditions to increase germination, prevent seeds from being washed away, or eaten by hungry birds.

Ideal Containers for Winter Sowing

One of the delightful benefits of winter sowing is that you can repurpose translucent containers to start your seedlings. The only cost involved is a roll of tape to reseal the container. Some containers will work better than others.

The best containers for winter sowing include plastic milk jugs, 2 or 3-liter soda bottles, plastic juice bottles, large water bottles, ice cream buckets, and other containers in similar shapes and sizes.

I have had success with other shallow containers such as rotisserie chicken containers, plastic lettuce tubs, clear deli containers, and disposable aluminum foil pans with plastic covers. These work well for small seedlings that are going to be transplanted while still very small.

I have seen some people plant the seeds in small containers (like plastic drink cups) and place them all in a large transparent tub or tote with ventilation holes in the top. Take advantage of whatever containers you have available.  

How to Get Started Winter Sowing

Enough about all the fabulous benefits of winter sowing, let’s teach you how to get started.

Prepare Your Little Greenhouses

Drill drainage holes in the bottom of the container. Seedlings don’t like soggy feet so this step is really important. If you don’t have a drill, you could use some type of sharp object such as an icepick. Just be very careful!

Slice your container about one-third the way up from the bottom but only cut it three-quarters of the way around. You will want to leave one side intact to serve as a hinge. I have found that it is easiest to accomplish this by using a sharp serrated knife but a sturdy pair of scissors can also do the job. I always wear cut-resistant gloves when I’m preparing my containers.

Throw away the lid! It is incredibly important that your little plants can breathe. The hole at the top of the container controls both the humidity and heat to prevents the seedlings from baking in the sun. If you are using a shallow container (rotisserie chicken or plastic lettuce tub) or a plastic tub, be sure to drill holes in the lid to ensure adequate ventilation.

Prepare the Soil

I use commercial potting mix for my winter sown containers but you can use your favorite soil as long as it is aged and has a high organic matter content. Seedlings need soil that allows them to grow strong roots.

  • Add plenty of water and mix it into the soil well. I like my soil to be a bit soppy when I first plant my seedlings.

Plant the Seeds and Tape the Container Closed

  • Fill the bottom of the container most of the way with moist potting soil and plant the seeds the depth recommended on the seed packet.
  • Tape the sides of the container completely closed. I like to use clear packing tape for this step but I have also used duct tape before in a pinch and both worked just fine.
  • Label each bottle with the date planted and the variety of seedling. I use a black Sharpie but by the time they are ready to plant the sun has faded the ink on the clear bottles. You may want to write on a small plastic plant stake and place it inside of the container.

Place the Containers in a Sunny Location

My favorite spot to place my winter-sown seedlings is on the south side of our home right next to the house. The south-facing location provides plenty of sunshine for my little seedlings and protects them from the high winds in our area.

Regularly Check Bottles for Condensation

Condensation on the inside of the container is a good sign and means that your plant is happy. The condensation level is a good way to monitor your plants for watering.

You don’t need to water your winter-sown seedlings very often, but don’t let them dry out. Reduced condensation inside the bottle means it is time to water them.

When to Start Winter Sowing

The best time to start winter seed sowing is in the late winter or early spring. It takes a little bit of practice to understand when it is the right time to start your seedlings. Variables that need to be taken into consideration include;

  • Climate, including zone and anticipated last frost date
  • Seed variety
  • Current weather patterns

I plant my cool weather crops such as kale, lettuce, spinach, and onions in late January through February. This year I waited until late February because we still had a lot of snow on the ground. I like to wait until the first thaw occurs and most of the snow has melted.

A snowstorm will not hurt your little seedlings. We always have a couple of good storms after I plant the seeds and they survive just fine.

A good rule of thumb is to check the back of the seed packet to see when they recommend starting the seeds indoors. I am comfortable starting the seeds a week or so earlier than recommended.

Our last frost date is May 30th so I will start my tomatoes, peppers, and basil the end of March or beginning of April. It takes a little bit of practice to get it just right but this process is quite forgiving. Make sure that you label each container with the date planted along with the variety so that you can learn as you go.

Give Winter Seed Sowing a Try!

I was skeptical before trying winter sowing and now I am a huge fan. Every year I save my containers and start my seedlings in repurposed plastic containers. Winter sowing is reliable, inexpensive, and produces fantastic seedlings with very little work.

Winter sowing is the poor man’s greenhouse. It can help you get a jump on your garden every year and just might be a highly valuable tool if you ever have to depend on your survival garden to feed your family. Give it a try!

Additional Greenhouse Ideas

Jonathan and I recently purchased the Food Gardener’s Video Workshop presented by Tom Bartels. We were very impressed with his video classes and are busy implementing his ideas in our garden.

One of the modules in his workshop is on season extension. He demonstrates hoop houses, cold frames, and other ideas to help extend the growing season for maximum food production. It is definitely worth checking out.

Thanks for being part of the solution!

Jonathan and Kylene Jones

Kylene

Kylene Jones is a blogger, content creator, published author, motivational speaker, homesteader, prepper, mother, and grandmother. She practices self-reliance, provident living, and emergency preparedness in her everyday life. She loves working with her husband, Jonathan, and is committed to helping our community be prepared to thrive during the challenges that lie in our future.