And thou shalt love the Lord thy God with all thine heart, and with all thy soul, and with all thy might. Deuteronomy 6:5
High Tunnel Agriculture
(Notes and slides from Dan Mielke's presentation)
tunnels may not give you more hours in a day but they will give you months of
extra hours in a growing season.
rain, sleet, nor snow shall prevent you from tending your appointed ground.
high tunnel reduces your work, increases your harvest, helps you beat out your
competition, and gives you the time to enjoy the work you love.
20’X 96’ tunnel
While the insects did affect the cabbage the damage was minimal.
Notice the health of the leaves.
Tunnel berries shown
Inside View of tunnel - pictured:
As foliage increases attention must be given to potential insect infestations and possible diseases.
Rope is used to keep roll-up sides from flapping in the wind.
Once the weather warms up, the end panels are rolled up or removed.
By simply turning the crank
It is important to make sure everything lines up.
Location! Location! Location!
You are the expert concerning your land and conditions.
Using the “High Tunnel”,
Tunnels in the Winter.
High Tunnel Agriculture
Tunnels: We averaged 30 man-hours to put up the tunnels including driving the anchor posts. Expect to add additional time if you have to assemble the hoops from pieces. While we liked the 26’ by 96’ tunnels better than the 20 foot ones, we found them much more difficult to put up due to the added height. Once they are up, the taller 26’ wide tunnels, are much more comfortable to work in. We did not even consider moving the large tunnels and bought two new 20 X 96 foot tunnels instead. They were much easier to assemble and move in midseason. While they were not difficult to move, we did find that the plastic did see some damage from the wobble wire and because we could not get the plastic back in the same area, the cover was weakened. To move the tunnels to the new location would take about 25 man-hours. If I were to do it again I would look into some sort of tracking system that would allow the tunnels to be moved forward and anchored as a complete unit. To do this you would have to have a large level area to allow for such a move. Keep in mind that it has to be anchored very securely to the ground to resist wind damage.
Strawberries: Berries were planted in 2002, during the summer, in the late fall, and in summer of 2003. They were planted in double rows under white plastic with drip irrigation.
We began the growing process on 4/15/03 by lowering the plastic to accelerate the growth of the berries. We needed no artificial heat during the entire berry season. We would put the sides down in the afternoon before sunset to hold heat in. In the morning we would elevate the sides to keep tunnel from overheating. One needs to be careful to not cook the plants, yet maintain an appropriate growing temperature. On cold nights we would also use floating row cover over the plants in the tunnel as an additional protection.
We were exceptionally pleased
with the results of strawberries grown in the tunnels.
iii. Less distorted
v. Had less pest damage
vi. All three varieties did well
i. Fair quality
ii. Severe turkey and coon damage
iii. Suffered frost damage
iv. Large amount of distorted berries
v. Honeoye was only variety that produced quality berries
i. King berry blossoms all froze
ii. Flavor was poor
iii. Berries were soft due to rains
iv. Berries all came in at once due to heat
v. Competition was severe at the market
vi. Most berries went to waste because of sudden ripening.
vii. Honeoye were only berry variety that produced quality berries
i. Early glow showed a 200% increase in tunnel
ii. Honeoye showed a 380% increase in tunnel
iii. Jewel showed a 330% increase in tunnel
i. Early glow showed a 22% decrease where no mulch was used
ii. Honeoye showed a 10% increase where no mulch was used
iii. Jewel showed a 50% increase where no mulch was used
iv. Berries began production and had heavier production in the beginning where no mulch was used
Berry production peaked at the same time in both tunnels
i. Tunnel one where leaf mulch was used between rows.
1. Late fall planting produced 42% of early summer planting.
ii. Tunnel two where no mulch was used between rows.
1. Late fall planting produced only 11% of early summer planting.
Berry sales were excellent, with
the one exception that we could not fulfill demand. The berries were early,
clean, large, extremely sweet and very aromatic. The customers noticed the
quality and commented that they were the best berries they had ever had. Picking
was at a slower pace due to a steadier ripening taking some of the stress out of
picking. Because of the
Saturday Farmers Market, we time pickings to be on Friday. On two of those Fridays there was heavy rain.
What a pleasure to be able to enter the tunnels and pick nice dry
berries. Had the berries been
outside of the tunnels, we would have lost all those berries or, at best, would
have missed our market day. In one
area, the ground was lower than outside of the tunnel and water did flow in and
damage a few berries. A few times it was hot and humid within the tunnels during
picking. Picking could be done
earlier in the day, due to lack of dew on the plants.
Raccoons and turkeys were a
problem both inside the tunnels and outside until we used a portable radio.
The test area out of the tunnels did not benefit as much from the radio.
We assume the echo within the tunnel enhanced the effect of the radio.
Lowering the sides at night also helped to avoid the early morning and
late afternoon raids by the turkeys as well.
We did not find any bees or
insects during the first blooming of the berries. But we did see a large number of spiders walking on the
blossoms. Later on, we found that a
very tiny type of bee and flies were quite active among the plants.
Very few honey bees or bumblebees were observed.
We used no mechanical pollination methods.
A lot of the insects that did enter the tunnels seemed to get disoriented
and were unable to find their way out. They
would fly up and bounce off of the top of the tunnel until they gave up or died.
The bumblebees in the fall were able to enter and exit without getting
We supplied about ˝ inch of
water per week during the fruiting season.
Possibly should have done more.
We observed no tarnished plant
bugs until towards the end of the crop season within the tunnels.
Outside the tunnels, we did observe more insect damage.
It seemed the early ripening avoided much of the typical fruit damage by
In the tunnels we did observe a
slight increase of slug damage and an increase of spittlebugs, but nothing of
Potatoes: We could
not screen out the bugs because the material we used caused the tunnels to
overheat. So we did not use any bug
barriers. We found no
marked difference between the tunnel and the test crop outside of the tunnels. No blight and very little potato bug problems were observed
on either test plot. This was
surprising, as we have always had bug and blight problems in prior years.
Potato color was excellent and size was acceptable. On a positive note,
we did notice that our Yukon Gold potatoes were the best we ever grew and they
had no hollow hearts. We may try some early potatoes next year but not a whole
tunnel full. Yields were the
same in or out of the tunnels.
some reason, the berries ripened quite late this year.
We did not get any ripe berries until September 26th.
On October 1st the
weather turned cold and our test plot outside of the tunnels froze, destroying
any hope of a berry crop. Being in
the zone 4 area , that is a common problem with fall berries.
The berries within the tunnels,
however continued to produce up until November 2nd.
There were two nights where we placed portable heaters in the tunnel.
We used approximately 20 lbs of liquid propane total.
The berries in the tunnels were of excellent quality and size.
The flavor varied depending on the temperature within the tunnel.
Sun and warmth play an important part in producing flavor. If a grower is able, he could enhance the flavor by spending
more time regulating the temperature during the day. I elevated the sides during the day to allow for bees to
enter, and often that allowed the temperature to cool off too much.
It is feasible to leave the sides down to maintain a higher temperature
within the tunnels providing one does not let the temperature get too high so as
to cook the berries.
We faced no wasp problems, as I
had feared. The primary pollinators
were small bumblebees, which did an excellent job. The canes kept blooming right up to the day the plants were
killed by cold in November.
Production was good up until the
end. The volume of berries on the
plants kept increasing up until the day they froze.
We decided to let the berries
freeze on the 2nd of November because the weather forecast called for
continued cold for over a week, and we felt the cost of heating the tunnel at
night would be too high to warrant us doing that for a prolonged period of time.
Turkeys were a big problem with
the berries outside the tunnel. A
transistor radio playing in the tunnel seemed to do the job of keeping critters
We gained 4 extra weeks of berry
picking through the use of the tunnels.
The berries sold well and had
excellent shelf life.
Other crops grown in
the High tunnels:
We were able to harvest about 20 lbs of tomatoes per plant using a determinate
beefsteak variety. The tomato
plants in the tunnel gave us a very clean, large, crack free tomato.
Flavor was excellent and the tomatoes seemed to have a higher sugar
content. Because the plants were kept dry, we noticed no disease
problems. Watering was done through drip tape laid under the plastic mulch.
tape is an excellent method of watering if you do not have running water
available. The tape requires very
little pressure and thus can be gravity fed by a water tank hauled to the site
on a trailer) I
strongly recommend plastic mulch in a tunnel, as this reduces evaporation and
allows for less stress on the plants. Caution
should be made to not plant tomato plants too close together as this could bring
about disease and pests problems. We
try to keep plants between 18” to 24” apart in rows that are 4’ apart.
Cucumbers are a great crop in the tunnels and the flavor is great.
Use varieties that do not require pollination.
Be sure to supply some sort of support for the vines to climb on. Water must be supplied consistently to maintain quality
and Possible Solutions:
Mielke's Farm Daniel@danielmielke.com
Jordan's Seeds, Inc