Tomato Hardening

After weeks of pampering our little seedlings in the warmth and comfort of the basement, it was time to bring them out into the real world. Ok, so the basement isn't heated, the walls are plain cinder block, there is no pretty ceiling, essentially a simple unfinished space. It's no four star hotel, but that doesn't bother our little friends one bit.

Typically the temperature stays around 65 degrees and while a little chilly, the tomato seedlings are fine with it. Of course this winter was a bit colder than most which left the temperature in the mid-50’s. The only way they survived through the chilly temperatures were the lights.  You need keep the little guys well lit (they need the food), which also results in measurable heat.  I decided to turn a corner of the basement into a grow room by walling it off with plastic drop cloths. Using a few cheap 4 foot shop fluorescent lights, which you wouldn't think generate a lot of heat, actually made quite a difference with the plastic drop cloths up. Within a few hours of putting the plastic “walls” up, the temperature in the grow room went from 55 degrees to 62. Ok, so there are more than a few light fixtures. Ten to be exact.

Another benefit of the “walls” was a nice rise in humidity. It quickly went from off the scale low to about 50% in a couple hours.  Plants like that. 

So for the past few months all the seedlings have been warm and cozy in their own room. Now it’s getting close to the time to move them out into the clay garden (that’s an on going story for us). We try to follow seedling hardening practices, putting them out for a couple hours a day, gradually increasing their time in the sun (not direct at first), and eventually leaving them out overnight. The sun, temperature changes, wind - basically nature - all work to get the seedlings ready for the long haul in the garden in a gradual manner. This year we have far too many plants to bring them in and out so a new strategy was needed.

Our deck has two levels (wait, this is not some fancy multi-level deck with a Jacuzzi and fluff - it’s a hard working deck with three Weber charcoal grills and a big Weber smoker), which lead to the idea of making a temporary greenhouse. A few 2"x4"s, some plastic sheeting, and one old screen door seemed like a good mix of supplies. Before putting all the plants out into the blazing sun a quick test was run, putting the pieces together into an amusing looking greenhouse, seen below.

Why the plastic? Here are some reasons:

1. Sunburn protection (not a great idea bringing plants into direct sun for an extended period of time, they really need to work up to full time sun).
2. Provide a little protection from the cold night (indoors they are used to a constant temperature all the time)
3. Keep our cat from playing with the plants while nobody is watching (if you think I'm joking, you don't own a cat)

Funny thing about #2: we've been on a nice pattern of increasing night time temperatures which gave us the false sense of security that things would be fine. The day we brought the first batch (80 plants) up to the deck, the forecast went to down to the upper 30's at night for a few days.

Now that we knew a simple outside home would be available, we brought up more plants and gave them their first outside experience.

After about an hour, it was time to add the sun protection. So we put the scrap 2"x4"s in place, along with a good watering.

Once the plastic "roof" was on, I had to peek inside.

Today we left the cover off until around 2:00.  They did require watering (and a little misting) during the day as our deck gets scorching hot. All in all, the plants have been doing fine inside their temporary home.  We are planning on moving them to the garden this weekend.

Tonight it's going down to 40, and 39 tomorrow (so say the weather forecasters), but I'm not too worried. The plants we've brought up are big and strong enough, plus the protection afforded by the make shift enclosure is sure to be sufficient.

A few trays of flowers were brought up a couple days ago, they were not given time to harden, and the sun has really rocked their world. They were looking tall and stately, now they're mostly laying down looking a bit pale. It also doesn't help that the neighborhood squirrels have taken to burying their nuts in the boxes.  Despite all the hardship, they are bouncing back and we expect them to do fine.

~Dennis