My name is Brittany Hunter. I'm a USU Extension Horticulturalist, and today I'm
going to show you some structures that we have in the garden to help us extend our
gardening season. We're standing at the USU Botanical Center in Kaysville, Utah.
The first structure I'm going to show you is a cold frame. You'll notice that there
is a slope to this cold frame and it's sloping so that it's facing the south.
We want this so we can capture the most solar radiation during the day, which is
what warms up the environment inside for growing our plants. You'll also notice
that in this case, a window is cracked and I will usually leave a little bit of a
crack in it so that the heat can escape. It actually gets so warm during the day
that we do need that extra ventilation and if it's not a window covering like this
one, you can use a stick to prop it open during the day and then close it down
at night.
We're going to use the cold frame for growing our winter salad crops so things
like spinach, lettuce, kale, chard, these are plants that can withstand freezing
temperatures and they'll keep very well in a structure like this and the size is
perfect for the very short plants.
This cold frame is also a raised bed, so having the soil raised up above the ground
level in a smaller volume means that when the sun hits it, it warms it up more
quickly and that helps our plants grow faster.
We were just looking at a cold frame which is good for growing short crops.
This structure behind me is taller so this would be good for growing plants like
tomatoes and peppers. It also fits over a raised bed so we get the soil
warming from that raised bed, and you'll notice the side here is open so just like
a cold frame it's going to get very warm very quickly as soon as the sun hits it.
So you'll notice on the end wall on this hoop house we have a metal clamp holding
open the door here and what this door is for is for ventilating the structure so
that it doesn't get too hot. This clamp does not use electricity, it operates on a
compressed wax within the cylinder which expands and contracts based on the
temperature and thus, will open and close this so that our plants stay at the right
temperature inside. These clamps are available locally at greenhouse suppliers
and online and cost anywhere from $35-$50.
So when we're ready to plant within this, what we're going to do is lift up the
whole thing. It's connected with a door hinge so that we can open it up to plant
inside and I just gently set it down. Now we can access the soil for planting.
We're planting on November first right now and these plants will be ready around mid
winter to early spring.
Ideally we would be planting late September to early October so that our greens would
be ready for a Thanksgiving to Christmas harvest. And then we'd let the structure
lie dormant and begin planting again in February.
So I have some little spinach plants here that I started indoors about three weeks
ago. You don't have to start your plants indoors, you can direct seed. But, you
want to direct seed when the soil temperatures are above 40 degrees.
Alright, now we're standing in our high tunnel here at the
botanical center and as you can see we can fit many more plants in a high tunnel,
and we can also walk inside the structure. What we have growing here is some
Bok Choi which is an excellent cold-season plant to grow. These were actually planted
in early October, and we will be harvesting them just before Thanksgiving
and could continue to harvest through Christmas.
If the overnight temperatures are below freezing you might consider using an
additional cover over your plants. This is called a plant blanket or a row cover cloth
It's not actually a cloth but it feels much like a cloth. It's a woven plastic
and if you can see it's very lightweight and plenty of light is able to penetrate
through this but it does keep the ice and the frost off of your plants.
Now that we've looked at three different structures you might be wondering which
is right for you. First of all you're going to need to have a sight in your
yard that doesn't get shaded in the winter months. That's very important.
I'll start with the cold frame and go over some of the pros and cons.
The cold frame is ideal for people who love to eat fresh greens. It also doesn't
take up a lot of space and it's a very simple design. The garden tunnel to my
right is ideal for those who want to start their tomatoes early or other warm season
plants so they need a little extra growing height and what's also nice is with this
design is that it has the automatic ventilation which is very important.
If you do have the space in your yard and you are passionate about gardening
vegetables you might consider putting up a high tunnel. There's a lot of
possibilities with the high tunnel and this one is 14 feet wide by 42 feet long.
A high tunnel is going to cost about $500 with this design.
The cost on the garden tunnel as you see here is $280, and $100 of that is the
automatic vent openers which are very valuable in that you don't have to
maintain it on a daily basis. The plants for the garden tunnel and also the high
tunnel are available on the USU website.