Thursday, March 10, 2011

What's New at the Farm? Greenhouse preparation

Johnny's Farm Manager Brian Milliken is on vacation. This week's guest columnist is Becky Traylor.

The lion of March has made its appearance. Sunday night we received about 2 inches of rain in temperatures just a hair below freezing, giving all the trees and bushes an icy halo. I do have to admit that even though I am ready for green grass, plowed fields and scarf-less days, I truly love the way trees look when they are covered in ice. Unfortunately, when you mix top heavy, ice covered trees and soft, water saturated soil a lot of trees end up coming down.

It’s days like today - when you can look out the window and actually watch the snow melt - that I really get the spring itch. Luckily, next week we’ll be firing up the first greenhouse of the season and starting the early seeding of grafting tomatoes. It always amazes me that it only takes a handful of seedlings to really get the ball rolling.

The greenhouse coordinator has only been back for a week, but she has already thoroughly cleaned and inspected greenhouse #3 so that it will be ready to go when we have seeds in hand. She has also been looking into ways of making the greenhouses more efficient. Efficiency in a greenhouse can start as easily as reorganizing the space or be as complex as automated, zone heating and watering. This year we are looking at better ways to water and fertilize our seedlings.

Watering here has always been done by hand, twice a day. Though hand watering is time consuming, it allows time to visually inspect the plants while watering. This way plants are constantly monitored and any issue can be handled quickly.

Flood benches are one option for automated watering that requires little daily time consumption. A flood bench is essentially a waterproof table with a water inlet and drain. This type of table is setup on a timer to allow a predetermined amount of water to flood the bench top, soak into the flats, and then drain out. Another option is overhead sprinklers or misters. Once the water line is set up, this system can be controlled by a timer and provides consistent watering. Automated overhead misting should only be used in greenhouses with excellent air circulation as excess humidity can provide favorable conditions for fungi and bacteria. Because automated watering reduces the amount of time spent with individual plants, it is very important to have a routine monitoring schedule. A monitoring routine should include inspections for disease and pest issues, nutrient deficiencies, and watering system malfunctions.

To help reduce nutrient deficiencies, we incorporate the use of fish fertilizers into our watering schedule. Fish fertilizers normally have nutrient levels that are mild and won’t injure tender seedlings but they are pretty heavy solutions that can have a hard time going through fertilizer injectors. Fertilizer injectors eliminate the need to mix fertilizer by the gallon, making the task of fertilizing more efficient.

Injectors work well with conventional soluble fertilizers like Miracle Grow or Peter’s but tend to be inconsistent with organic fish based fertilizers like Neptune’s Harvest. One of the reasons that fish fertilizer can be inefficient in an injector is that the heavy solution tends to settle, floating the oils to the top and dropping the solids to the bottom. In order to get the true nutrient levels from this emulsion, it must be stirred or agitated regularly. Another reason that fish can be troublesome for an injector is that it leaves an oily residue on the tubing and moving parts of the mechanism. Over time, this residue becomes sticky and can clog the lines and inhibit the movement of mechanical parts. Since most organic fertilizers are fish or seaweed based, it can be hard to find a solution that works with dilution systems.

In the up coming weeks we’ll be testing a handful of organic soluble fertilizers as well as starting our first seedlings of the season, ordering last minute supplies, finishing up our season’s planning and I’m sure that we’ll have to move some more snow. In the meantime, I for one will be hoping for 35 degree sunny days with a nice drying breeze.

1 comment:

Pure-N-Simple said...

Green house efficiency is one thing I am focusing on my little custom made greenhouse, last year I heated it with just a propane heater, and this year was thinking about incorporating a wood stove, not sure though, nothing like waiting to the last minute- right.