That Time of Year

April is distracting, isn’t it? The house finches are plucking coconut coir from my hanging baskets to make their nests, the yellow-faced bumblebees are in the borage, and the clematis ‘Montana’ is a froth of pink. Nature is in the midst of transition.

And so is the garden! This is the time of year when the tomatoes and pepper seedlings have to be taken out of the ‘greenhouse’ every morning, and returned back every night. It’s still too chilly for them to be put into the raised beds, so they need to be babied a bit. Oh, it’s hard to wait.

But they’re still too little, and the soil too cold. However, other things can be planted! I’ve removed the lingering cauliflower, cabbage, chard, broccoli, and beets; in their places I’ve planted potatoes (Yukon Gold, Huckleberry Gold, and German Butterball), pole beans (Rattlesnake, my favorite) and the dry beans from Rancho Gordo. I’ll wait until May to plant cucumbers, basil, and winter squash.

We’re still eating peas, both shelling and snap, nearly every day, along with asparagus (six years after planting the most recent batch of crowns, and we’re finally getting all we can eat). Artichokes are coming on, and the herbs are going crazy - the oregano and marjoram and sorrel just overtaking their beds, and the chives and culinary sages blooming beautifully purple!

And the flowers… well, the flowers are abundant. Borage, and poppies, and phacelia, and heuchera, and columbine, and salvias, and echium…. the list goes on and on, and I haven’t even told you about the fruit trees and bushes yet. Summer is coming!

What’s happening in your garden?

Greenhouse Thermometer

Our greenhouse isn’t much to look at, just some old redwood fencing and plastic sheeting that we repurposed with the help of my dad, but its creation several years ago revolutionized my efficiency. Tom went to the trouble to figure out mathematically how to build the shelves inside to best capture the angle of the sun, particularly in winter. I don’t have anything in there right now, but starting March 1, the first batch of pepper seedlings will need to move in here to make room for tomato seedlings in the house. I’ll also start a lot of flower seeds, and squash/melon seeds at the same time, and just keep them in the greenhouse.

In an effort to maximize efficiency, I decided to buy a cheap greenhouse thermometer from Govee. This has allowed me to see, from my phone, the temperature and humidity inside it, without opening the door and letting out all the heat. If you allow Govee to have a lot of information about you, you can also make some neat charts and get a history of temps over time, wherever the thermometer is placed. I didn’t allow that, but I’m still able to collect enough data to get an accurate picture of what’s happening in there. Last week, I added a bowl of water to see if that would affect the humidity. I’m not sure it has, actually. But the data is interesting and it caused me to ask some more questions about humidity and its relationship to heat.

Here’s a morning reading:

You can see that temp and humidity are at about the same level.

Now, here’s an afternoon reading (the door is closed, remember):

Notice how, when the temperature rises, the humidity level goes low. I couldn’t figure this out, so I asked Tom to explain it to me. That allowed us to do some research together about it. Now, I know some of you probably already know this, but I did not, and I’m guessing some other folks don’t either. So bear with me as I share what I learned.

Relative humidity represents a percentage of water vapor in the air that changes when temperature changes. Warm air holds MUCH more moisture than cold air. So when it’s very warm, the air is ‘holding on’ to the moisture, and when it’s cool, the air can’t hold on to it, releasing it into the atmosphere. For instance, a rain cloud can only release its moisture when it cools down enough. That’s one of the reasons rain clouds are higher in the sky - it is colder as you get higher. 100% humidity makes a cloud, but it won’t release water until it’s cold enough to do so.

So, roughly, when the air in the greenhouse is at a very high temperature, it is ‘holding on’ to the moisture and I get a low humidity reading. But when it cools off at night, the air ‘releases’ the moisture, allowing it to be read by my thermometer.

Does that make sense?

Now, when there are plants in the greenhouse, they will be photosynthesizing; taking the sun’s energy and converting it to sugars to be taken to the root of the plant. While this is happening, the plant is transpiring - releasing moisture from the leaves. Photosynthesis ‘pulls’ the water up from the root of the plant to the leaf of the plant, where it is released into the air (there’s a complex process of using some of the water in the process of photosynthesis which we can leave out for the purposes of this conversation). Will this increase the humidity in the greenhouse? It won’t be happening at night, because there is no photosynthesis at night (for the most part - some plants do this but not the ones I’m talking about, usually only desert plants). It will be interesting to see the results of that.

The thing to remember is that air circulation is the MOST important thing about greenhouse management. If the air doesn’t circulate, the plants will have too much humid air around them, therefore they won’t be able to make any more water evaporate, and that means no nutrients will be coming up from the soil. So open your greenhouse doors during the day when plants are in there, no matter how much you want to keep them closed. Open the greenhouse during the day and close it up at night to keep things warm and snug.

Heading

Growing heirloom winter wheat has been such an interesting experiment. Grains are an excellent rotation for any cropping system, as they build soil and feed microorganisms with their extensive roots. They prevent erosion, cover the earth, and provide a great deal of biomass that can be used as mulch or compost material. There's very little pest pressure.  And, if you're lucky, you get a crop on top of all that.

Our wheat crop, which was 'lodging' (or falling over) has righted itself and is now 'heading.' The plants generally go through an aggressive growing process in early spring, then form a type of leaf called a 'flag,' which is easily seen in the above photo. The flag leaf produces a shaft wherein the grain begins reproduction. Those flowers you see are self-pollinating, and after the pollination process, seeds will form.

I grew up near farming communities on the east coast, but I don't ever remember seeing grain. I know very little about it. I imagine if you grow up in the mid-west, you're very used to seeing these crops. I have had a good time researching how wheat grows; I've needed to consult the experts at every stage. It's evident that my crop is heading quite a bit earlier than wheat usually does in our state, early April being the common time. We had very warm temperatures for about two weeks in early February, which I think triggered the plants to begin reproduction. February 15 is our last frost date, so I'm hoping that it won't get too cold now (temperatures have dropped!), and that the seeds can withstand that chill. If they do withstand it, this early heading is a great thing, because I might just get a small crop in before I plant out tomatoes in May. Normally wheat isn't ready to harvest until late May or early June here.

When the plant has set seed, it will start to brown and dry up. Then I will know it is time to harvest, sheave, and then thresh. Of course, the right amount of water is very important now, so I'm glad we have an irrigation system, as it hasn't rained here for the entire month of February, and actually I don't remember getting any significant moisture in January either. 

Meanwhile, I'm in the process of potting up over 200 sunflower seedlings. I may have overdid, just a little.