fan installed and incredible growth continues

I finally installed a fan on the growing shelf to help circulate the air. 

Small fan attached to the greenhouse structure on the growing shelf blowing air just above the tops of the plants:

I'm thinking that this will be useful in two main ways.  One, keeping the air moving should help to prevent all the hot air from rising to and staying at the top of the greenhouse structure.  Two, it will prevent stagnant air in the greenhouse.  Stagnant air can allow pest problems and mold to develop, and also can starve the plants of CO2.  In the Greenhouse Gardener's Companion, Shane Smith writes that in still air a plant can draw out most of the CO2 just above the surface of its leaves, creating an envelope of CO2 deficient air.  Adding a fan to stir up the air around the plants prevents this type of CO2 deficiency.  It also helps to strengthen the stem and roots of the plant by mimicking wind.  This is especially important if the plants are going to be transplanted outside later.

The second batch of Dukat dill on the germinating shelf has really taken off.  I have no idea why more of the seeds didn't germinate the first time I planted them, but they are doing fantastically this time.  They have all put out their primary leaves, and probably will need to be transplanted soon.

Dukat dill on the germinating shelf:

They have already surpassed in height the lone dill plant from the first batch of seeds.

All the plants on the growing shelf continue to exceed my most optimistic expectations.  An excerpt:

Oregon Spring Bush tomato:

 

Crimson Sprinter tomato:

Red House Free Standing tomato:

 

Santiam tomato:

Maglia Rosa cherry tomato:

Chadwick cherry tomato:

Fox cherry tomato:

Pimientos de Padrón:

 Purple Opal basil: