The Rusted Garden Journal : Using Shelf Greenhouses to Start Your Gardening Season Early: Transplant Acclimation

Using Greenhouse Shelves to Acclimate Your Indoor Plants to the Sunny Outdoors

(A Joint Approach With Indoor Seed Starting)

A basic standard shelf greenhouse will help you get your garden off to an early start. They are excellent for starting cool weather crops outdoors like lettuces, spinach, kales and onions when the nights stay 30 degrees or above. Cool weather crops like the cool and colder weather and can handle frost. Below is an example of a shelf greenhouse that can be put anywhere in your yard.

I spent $30.00 on the example below from Big Lots. I found the same item packaged under a different name at Home Depot for $24.99 and you can find them shipped at a cost of $30 to $45 on Ebay. This exact model is used in different packaged boxes. You can identify it by looking at the design of the plastic pieces the metal tubing inserts to on the sides.

Because of the shape, strong wind can blow it over. I suggest securing it to a deck post or railing or by putting rocks or milk container filled with water on the bottom shelf to help keep it stable. It can easily hold 6 cell flats which equates to a lot of seedlings and transplants.

You can also spray paint milk containers black and let them absorb the heat from the sun during the day. They will release the heat at night to help manage temperatures. I will write more about that in March.

A good way to use a greenhouse shelf unit with seeds started indoors during very cold days (when nights are still under 30 degrees) is to put the flats out in the shelf unit during the day as soon as you notice germination starting indoors. Why? Well you can actually begin to acclimate your indoor plants to the outdoors while they are young and just sprouting.

A sprouting seed expects to find full sun so it is protected. It is only after it grows weeks indoors that it loses its ability to manage full sun. By putting the newly sprouted seeds outside in the sun... you are acclimating them. You should also put them outdoors regularly as they develop. Just bring them inside during the late afternoon and evening and let them grow indoors under house heat. This is a great way to grow and prepare your transplants for the great outdoors. They will be strong, fit and your garden will get started weeks early.