Hopefully some you have had a chance to order seeds for spring planting. If you haven't done so as of yet, it makes sense to order the seeds for this upcoming fall as well. That's if you already have an idea of what you want to follow those tomatoes when they come out of the ground. The main thing in the short term is to be ready to plant in about two weeks.
In the handout that was sent around for spring crop suggestions, I picked easy to establish, direct seeded, short day varieties to try. The main factor to consider is that we ideally want those crops to be harvestable around May 15th when the summer tomato crop will be ready to go in. However, because the tomatoes are transplanted and tall, it will be possible to inter-plant them; meaning you can plop the toms right in amongst what is already growing there. The same can be said for over-wintered spinach. You have the option of planting something tall like peas right down the same bed as the spinach is growing in. The three crops that I proposed for this spring were radishes, salad mix, and peas. Radishes and salad mix are pretty straight forward and simple to establish. But, peas will need a trellis to climb.
Trellising for peas can be as simple as some 4ft. long wooden sticks driven into the dirt and twine strung from stake to stake. I prefer to use 4ft. metal fence posts and chicken wire. It is easy to erect, sturdy, and can be re-used year after year. Because they will be grown in a greenhouse environment, the peas will most likely grow much faster and taller than outside. Another consideration would be to send down a plastic snow fence or deer fence type of product from the frame of the high tunnel. How you attach it and over all height will be a factor for finding the right product in that case.
Hopefully the ground will not be frozen and ready to plant peas in around March 15th. You will definitely want to keep row cover on them as much as possible to protect them from night time frosts. Even after erecting the trellis, you can still drape the fabric over the top to create a tent. As for the radishes and salad mix, I would wait until the last week of March or first week of April to sow those seeds. If your over-wintered spinach is doing good, you can harvest that two to three times and can stay in the ground until tomato time if you want.
Happy planting and don't hesitate to ask for help!
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