21 January 2008

Normal Average Weather, Coldframes

Northeast Oklahoma's growing conditions change every year. Normal average rainfall is 44-inches which makes many high country plants swoon from the humidity. Mexican sage, lavender , penstemons and many bulbs dislike high humidity and having their roots too wet.

The area's normal, average temperatures include 70-days a year at 90-degrees and above, plus 70-days a year at 32-degrees and below.

We are in USDA cold zone 7 and American Horticulture Society's heat zone 8.

These are the factoids we need to take into consideration when planning our gardens for spring, summer and fall. Read catalogs and plant descriptions and try to give plants the conditions they need to succeed. If the catalog says "good drainage" put the plant in a raised bed, on a slight slope, amend the soil with sand or perlite or plant near the thirsty roots of shrubs and trees.

Two resources to keep handy: 1) Tulsa Master Gardeners website and 2) Oklahoma State University Horticulture. Both of these sites have answers to questions you did not even know you had.

The ground is frozen and nothing can be done outside so these flower photos from last March will have to get us through until winter passes. Remember two years ago when there was not one day of freezing weather? The outside work never took a break that year.

Photos: Native violets on the left and Leucojum blooming on the right.

Hotbeds and Coldframes have been taking up some of my research time for the past 6-months. I'm not sure I need them now that the shed provides a protected place to raise seedlings under grow lights.

But, what about hardening them off in a coldframe for 3-weeks before planting out? Maybe that would increase their survival rate.
North Carolina State University has a fact sheet that explains the basics.
Home and Garden Television has some simple construction tips.

Do you have an outdoor cold frame or hotbed? If so, do you use it very much? How was it constructed? Any advice for those of us who are considering building one? How big for a starter coldframe? Is yours dug into the ground 8-inches deep as recommended by NCSU and HGTV?

3 comments:

Anonymous said...

HI Molly,

Here are some answers to your questions.

Do you have an outdoor cold frame or hotbed?
I have several coldframes.

If so, do you use it very much?
I use mine year round. In the winter I grow vegetables such as lettuce in some of them. I use them for winter seed starting. I plant the seeds in flats and put them in the coldframe. As long as I keep them watered they germinate on their own and are generally much stronger than ones started under light.


How was it constructed?
A wood frame and 6 mil. plastic.


Any advice for those of us who are considering building one?
What are you waiting for? Really - I absolutely love mine!

How big for a starter coldframe?
That depends on what you are growing. Mine are generally 6 ft. by 8 ft. by 8 ft. but I do have some smaller ones.

Is yours dug into the ground 8-inches deep as recommended by NCSU and HGTV?
No, mine sit on top of the ground and I am in zone 5/6 - Indiana.

Sheri
http://www.exoticgardening.com

Dee/reddirtramblings said...

I've thought about building cold frames, but then we'll have one of those years with no freezes, and I think they are worth the trouble. Definitely would need an automatic opener. Our weather is too unpredictable.

Martha said...

Sheri
I'm going to have to come to exoticgardening.com and look for photos of your cold frame for reference.
Your post makes them sound very valuable for greens growing.


Dee-
Hi! I know what you mean. At master gardener conferences those who have been growing for decades (unlike me) say that all we need in Oklahoma is a cold frame - never a greenhouse per se.

But, then when you listen to John Leonard who grows veggies in OKC practically year 'round, the whole effort is tempting again.

We shall see. I'll check out Sheri's.