Good morning, and sorry I asked. Welcome to Saturday Morning Garden Blogging.
So, last week I was complaining that we here in Denver had not gotten our customary January thaw.
Nature answered.
The Arctic Express roared into town on Wednesday, so now it's been really cold.
Single digit lows. Highs that don't come near to freezing. And yesterday, to add insult, it was cloudy and damp and felt even colder.
It started snowing right as I got home yesterday afternoon — not a lot, though, because it's too damned cold.
Forecast says we may get above freezing by next Wednesday. But, alas, no January thaw. Again, sorry I asked.
But hey — the first of the forced hyacinth are blooming!
Isn't it fascinating to see those tiny little tips of purple on the stamens, and the color-coordinated pistol? Now I'm waiting for some different colors to bloom, to see if that color-coordination follows through: do pink hyacinth have reddish pistols, and red tips on the stamens?
We're getting close to seed starting season, so I thought I'd talk a little bit about light — specifically, the need for artificial light.
The bad news is that there are few people in the northern portion of the States that can start seeds indoors without supplemental lighting. Even if you have huge southern-exposure windows, odds are that your seedlings will end up leggy if you rely only on what natural light is available this time of year. The exception might be if you have a bay window with no overhang, so it captures light for the majority of the day.
Part of the problem is the day length and angle of the sun. Winter sun is weak because of the low angle. The hours of daylight are fewer. And you're trying to trick plants into thinking that it's later than they think.
The good news is that you do not — repeat, do not — need to buy expensive florescent "grow lights" for seed starting. It has to do with spectrum, and what you're trying to accomplish. Here I turn to the Oregon State Extension Agency:
Blue and red light, which plants absorb, have the greatest effect on plant growth. Blue light is responsible primarily for vegetative (leaf) growth. Red light, when combined with blue light, encourages flowering. Plants look green to us because they reflect, rather than absorb, green light.
Knowing which light source to use is important for manipulating plant growth. For example, fluorescent (cool white) light is high in the blue wavelength. It encourages leafy growth and is excellent for starting seedlings. Incandescent light is high in the red or orange range, but generally produces too much heat to be a valuable light source for plants. Fluorescent grow-lights attempt to imitate sunlight with a mixture of red and blue wavelengths, but they are costly and generally no better than regular fluorescent lights.
Put simply: when starting seeds, you are trying to encourage leaf growth — exactly what cheaper, standard fluorescent tubes do. The other thing you'll need is a way to raise and lower the lights, so that they remain just a couple of inches about the seedlings.
So go down to the hardware store and find an inexpensive shop-light rig that will hold a few fluorescent tubes. If you have a good locally-owned hardware store (rather than a big box), they'll likely be happy to help you figure out how to set up a stand so you can raise and lower the lights. And I'm sure you'll come up with something that is much, much less costly than the rigs available at Gardeners' Supply Co., where the least expensive item is priced at $199.
If you are going to be keeping seedlings inside for more than 6 or 8 weeks (that is, if you're starting them really, really early), you'll likely want to invest (and it is an investment) in a metal halide light rig. They provide light that is much more intense than that available with fluorescent lighting, enabling you to plant out tomatoes that are a foot high, rather than a few inches. I have a 400-watt metal halide light, which gives enough light for an approximate 6 ft. x 6 ft. area.
That's what's happening here. What's going on in your gardens?