Dirty Little Greenhouse Secrets Revisited

The primary components of a working greenhouse are damp and dirt.

Dirt is a given. Potting soil does not stay in pots. You know those fancy pictures you see where everything is spotless and the floor is white? Count the plants: a few perfect ones for decoration. If those are your aspirations, you want a conservatory with a writing desk and a place for tea, not a greenhouse.

I do a lot of hand watering. Do you heft your pots to see if they're lightweight? A heavy pot may be water soaked and not need a general spraying with the rest.


Cachepots are not just for decoration. Plants in a plastic pot get top-heavy. In a cache pot they're secure and can be lifted out to water and drain, repot, dab with an alcohol-soaked q-tip for bugs, or whatever. The space between a thin plastic pot and a cache pot helps keep cold drafts off the plastic pot. A recycled glass jar inside a cache pot is a good place to root cuttings. A plastic container sitting in a ceramic cache pot is bound to have warmer roots than in a thin plastic pot sitting on a wood shelf.

Thermal mass helps mediate daytime heat to nighttime cold. There is not a way to keep a greenhouse above freezing in a cold winter without supplemental heat in some form. The easy, less expensive way is a couple of heaters from the big box store. Be sure they have high and low settings and a thermostat. You must use the low setting if you want your heater to last as long as your greenhouse. It takes some trial and error on cold nights to get the thermostat set 'just right.'

Behind the center group of plants is a piece of styrofoam that was packing for something we ordered off for. It is recycled as insulation behind this group, on the north side of the greenhouse where it reflects light coming from the south and west.

Heaters take space. Remember I said a greenhouse needs two? Better one still running if one goes out than a big heater that hasn't a back up when it fails. I didn't mention adequate wiring; it is important. Here's the thermal mass part: There are charts online that give the information about what substances are most useful in holding heat generated by the sun. Water is most efficient. If  you can get some barrels for water, hooray! The barrels can have a shelf on top to offset the floor space they take up.

Each plastic gallon jug of water used will help a little bit. I fill mine and line them up in front of the heaters, usually about 8 or 10 jugs for each heater. Heaters and water sit on the walkway. When the weather warms, heaters go back in the tool shed and I water plants from the jugs and put them in the shed until the next cold spell. The hot air blowing on the water jugs warms them and the heat is given off more slowly than the hot air all rising to the ceiling as the heaters blow on nothing. That's my theory, you may  not agree.

What else helps with heat mediation? Remember those cache pots? Ceramic material, bricks used as plinths, stones, pieces of concrete -- all these are helpful to hold heat. Sun shines on them during the day; later when heat is needed as the air cools that heat is given up.

I read this week about heating with compost. There isn't that much room in my greenhouse. I don't know of an feasible inexpensive, nearly free way to heat. I address keeping plants from freezing here, affordable but not cheap. I keep my orchids in the house where it's warm.

 

Divided the Guzmania. Two plants  replaced the old one; both those had pups

around them and now the pups have pups. Bromeliads have life cycles.

Too much is never enough. You'll never have enough space or too many kinds of plants. You may eventually have too many of one kind. Share with others.

Plants tend to grow. The little Birds Nest Fern of a few years back now takes up nearly 7 square feet of GH floor space. Sometimes I let plants bunk together, like Purple Heart and Persian Shield in a container together, or Foxtail Fern and Chlorophytum.

 

A 2" pot of Burro Tail yielded 7 pots full 

in under 3 years. Plants grow.

Frog Poop. The best pest control in a greenhouse are little toads, peeper frogs and lizards. They do donate their little share of fertilizer and it isn't always pretty. Sometimes when I add water to the cup of a bromeliad, a tiny green frog emerges. Cachepots are places for frogs to hide. The greenhouse is alive.

Persian Shield in bloom in winter.

It isn't really work. There are plants that find just the right time to bloom when the days are short and they're hanging out in your greenhouse. I would never otherwise have seen blossoms on Burro Tail Sedums or Mistletoe Cactus and probably not on White Shrimp Plant and Persian Shield.

Burro Tail Sedum winter blossoms

Rhipsalis blooms, midwinter

Rearranged the Greenhouse Furniture

There isn't that much room to begin with. Plants tend to hang out over the walkways. Esthetics begin to plague me. We must be able to walk all the way around and I have to reach everything to hand water.

The shelf unit was against the shelf on the north wall. Changed it out with

the little table in the center. It has hardly a larger footprint than the table and

a metal stool on which a tall plant sat. The metal cart that partly blocked

the door is now in the back. I've covered part of the patchwork floor.

 

My thinking was that the shelves are taller but their openness keeps them from looking  as bulky as I'd feared. Trays of seedlings and cuttings can get sun here while tall plants sit on the top.

 

 

The ability to walk all the way around whatever is in the center

is primary. The camera caught the ventilating fan in a way that

it doesn't appear to be turnng but it was.

 

Tomato plants lean against the water barrels behind a burlap skirt.

 

I was reading formulas for figuring how muich thermal mass per square foot.

We need three times as many barrels for most effective temperature

mediation. If I had 8 more barrels, we'd have no room to walk around.

We'll just make do with supplemental heat. Two small heaters on low

have worked well to keep plants from freezing in our coldest winters.

 

 

We ate a tomato tonight that

I had tossed into the basket where compostables go when it fell

off the vine. I thought it too small to ripen. I knocked the basket over

today and the ripe tomato rolled out. Tiny, but tasty.

 

 

Here's Ike in his wicker perch surrounded by Epipyllums. They are the

bulkiest plants in the greenhouse and awkward to place. Ike's pot of

Lemon grass is the red one in the center. It helps keep him from

shredding leaves of whatever is near him. He loves to shred Bromeliads.

 

 

A sudden rainshower caught me inside, so I made pictures.

This is a homemade fogger with three nozzles. It helps with

climate control, both humidity and summer temperatures.

 

I want to move the potting bench farther toward the back so

that it doesn't get so wet when the fogger is in use. I measured

and it looks as if the shelf unit will fit into that space.

Sounds to me like a summer project since I don't want

tender plants on the north wall now.

 

The entire water system:

a single faucet with a Y which controls

water to the fogger on the left and a short

hose on the right that I use to fill watering cans.

 

We put the greenhouse together late in 2007.

We've made it work.

 

 

Green tips have emerged on all the hyacinths.

I used to set pots of forcing bulbs in the utility

room sink. This is better.

 

This is the only seat right now other than the step

stool that I use mostly to reach plants that are too

high for me to water from the floor. I sat there

until the rain shower was over.

This is a little bench that my late father in law built.

 

Today was unusually warm for January. I'm always concerned that we'll get a storm with high winds when there are warm breezes from the south. Fortunately the rain was straight down, no wind.