This season we built four high tunnels on
an urban brownfield – a former gas station on Vernon Drive. The first two
houses are growing some luscious tomatoes.
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Sweet Sungolds! |
So many delicious varieties - Indigo Rose,
Moskovich, Big Beef, Black Cherry, New Girl, Striped German, Green Zebra,
Yellow Pear, Pink Beauty, Tomatoberry, Yellow Mini, Favorita and Sungolds. Oh
goodness, the Sungolds. These are the Farmer’s Market secret weapon – rarely
does someone taste a sweet Sungold and make it far from the tent before
purchasing a half pint. They are like candy, straight from the sun.
We were super late with the construction of
the green houses – like two months late – which meant by the time we were able
to get our tomato plants in the ground they were pretty hurting. The plants
were leggy, wilted and purple in colour as they were so deprived of space and
nutrients. We weren’t sure if any of them would make it but discovered that
tomatoes are truly resilient plants.
We planted them fairly deep in the soil,
partly to give them stability in their weakened-stem state, and to help with
strong root growth. We loosened the roots of each plant to ensure that they
weren’t root bound or tightly coiled. Root bound plants rarely make it.
Each of our planter boxes had two staggered
rows of plants, 12 inches apart. Because the plants were so weak, we also
picked off any flowers that the plants had at this point to ensure the plant
focused its energy on producing strong roots and stems. Once the plant was
better established, it could begin to flower. We also foliar fed our plants
with a kelp fertilizer to help them make it through the transition.
Determinate vs. Indeterminate:
Tomato plants are classified as either
determinate or indeterminate. Determinate plants will bloom and set fruit once
in a season. They are often more compact which makes them great for container
gardening. They do not continue to grow throughout the whole season – they
fruit quick and then begin to diminish. This also makes them great if you want
a large volume of tomatoes at one time for making sauce or canning. Determinate
tomato plants do not get pruned, as they get need to be able to support lots of
heavy fruit at one time.
Indeterminate plants continually bloom and
set fruit throughout the whole season. They are vining plants, continuing to
grow until they meet frost. These plants are the ones that get regularly pruned
of suckers and require some vine support such as staking, or in our case,
trellising. The tomatoes we grow at the farm are indeterminate varieties. We
are able to trellis them neatly in our greenhouses and are able to have a
steady, continual supply of tomatoes through the season for our markets.
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Trellising drawing from my notebook. |
What I’ve Learned About Trellising:
We ran wire along the length of our
greenhouses. We then cut baling twine so that it was twice the length of the
height between the plant and the top wire. Tie a loose slipknot around the base
of the tomato plant with one end of the twine. Toss the other end of the twine
up over the top wire and pull it down to tie another slipknot with that end
around the twine. You can then tighten the length of twine using that top
slipknot. Begin to gently wind the main stem around the twine as you tighten.
Be sure to loosen the bottom knot as the plant grows and the stem gets
larger. You can tighten or loosen the top slipknot to adjust the tension of the
twine if needed. Check out my charming drawing if the explanation isn't too clear.
What I’ve Learned About Pruning:
When the plant is fairly well established
you can begin to prune. First, start at the base of the plant and follow the
main stem all the way to the tip – this will help you identify your leader,
leaf branches and suckers. That main stem running from the base of the plant to
the very tip is your leader.
I find it’s easier to start pruning from
the bottom. Hold on to the main stem and look at the first leaf branch – check
out the elbow between those two, if there is a new branch in the elbow where
they meet, you’ve got a sucker! When they are small, just pinch them off with
your fingers close to the elbow. When the suckers get big you will want to
prune them with a small knife to ensure you don’t damage the stem or leave an
open wound close to the main stem – leaving it more vulnerable to disease.
Suckers will draw energy from the plant, so removing them removes the energy
demand and helps the plant focus energy on fruit production. Also, removing
suckers allows for better airflow around the plant which helps with disease
prevention. You can also remove any new growth below the leaf branch, or even a
few bottom leaf branches to ensure that the leaves are not touching the soil – again
this helps with airflow and deters the spread of disease.
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Pruned and soon-to-be trellised. |
When you get to the top, it may be
difficult to discern which is the leader and which may be a sucker – its ok to
wait a few days to see how these develop. If you have two branches though, know
that the flowers always form on the leader first, and then on the sucker. So if
you are holding onto a branch that you think may be a sucker – look at the branch above it, if that one has flowers, you most likely are holding onto the
sucker.
Always be careful of the growth tip of the
tomato plant – you never want to prune that or damage it, as that is where new
growth happens. If you top the plant and remove that growth tip, your plants won’t
continue to grow.
Pruning also leaves your hands smelling
delicious and turns them a darker colour that is hard to wash off.
Hot and Dry:
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Mixed cherry tomatoes. |
The high tunnels are unheated poly tunnels
with roll up sides. They get mondo hot during the day, and tomatoes love hot
and dry climates. We aren’t dry farming, a technique where irrigation is cut
off after plants begin to fruit, but we are keeping the watering to a minimum
(partly due to not having a water source from the city for a few months and
having to haul water from the fish plant across the street). Dry farming causes the plant stress out, send roots deep to look for water
and focus on fruit production to ensure its survival in the form of seeds.
The result is tasty fruit. Some critics say this also can lead to blossom end
rot and cracked tomatoes if you aren’t able to successfully control the
watering (ie. rain) and there are drastic fluctuations in water availability. The
relatively warm dry microclimate of the high tunnel does mean our tomatoes
taste fantastic!