Seed Starting Series: Grow Lights, Heating Mats and Maybe a Greenhouse?
This is a photo of my first 6x6 baby greenhouse and what a dream come true it was, but it was a long time in the coming. For many years, I exclusively bought seedlings from my local farmer’s market and trusted nurseries, which I still think it is a great practice for lots of reasons! Here are just a few:
Supporting local, organic farmers is incredibly important to protecting the health and biodiversity of our local food supply. Here is a great article by the Rodale Institute that discusses this further.
It saves time and growing space.
As a new gardener who was also a new mother of very young children, buying starts was frankly just easier and it enabled me to spend less time in the winter/spring sowing seeds. I was able to get my whole garden planted over Memorial Day and focus on tasks like feeding, watering, weeding and best of all harvesting!
However, it wasn’t too long before I knew that I wanted to start my own plants from seed. Here in Colorado, we have such a short growing season that I found I really missed having my hands in the soil during the long winter months. More importantly, I had started looking at seed catalogs from Botanical Interests, Baker Creek Heirloom Seeds and High Mowing Organic Seeds and I knew that I wouldn’t be able to find the majority of the these unique, exciting seeds at the farmer’s market much less my local nursery so I took the plunge and I started to grow seeds in little seed starting kits like this. And you know what, to begin with, they worked great. I was really successful growing easy crops like salad greens etc., but over time the three main reasons I stopped using them was the cost, the unsustainability of it the product (plastic trays weren’t strong enough for multi-use over the years), and I found that I kept having the following issues with the plants I was most interested in growing:
Lots of seeds didn’t germinate no matter what I did! It turns out that some seeds need a consistent soil temperature (often on the warmer side) and the “sunny window” had huge temperature fluctuations, getting too cold at night. Seed packets often have an ideal temperature for germination and having heating mats enabled me nail that without the hassle and guesswork required otherwise.
My seedlings would end up thin, a little on the weak side and “leggy” or too tall for the number of leaves that they had. I found out that this happens when little seedlings are reaching for a light that is either too weak or too far away. The best way to solve this is by putting grow lights several inches (rather than several feet) above the tiny plants and raising the lights as the plants grow. The other advantage of using grow lights is that you can ensure your seedlings get at least 16 hours of light per day. While many gardeners leave their lights on 24 hours a day. I turn mine off so that I don’t create light pollution for my neighbors.
If you can relate to the above then I recommend starting with one plastic or rust-proof metal shelving unit and buying heat mats that fit on each shelf and grow lights that can be raised and lowered as you need them to. If this unit will be indoors then I recommend getting a thick waterproof mat for underneath as watering spills are inevitable.
For lights I recommend T5s which are a full spectrum fluorescent bulb that are a bit thinner than the regular size which helps with plant coverage. Alternatively, I recommend LEDs designed for growing plants. I am transitioning to them this year due to their energy-saving features. I’ll keep you posted on how they work for me but my gardening friends really love them.
For heating mats, I use the ones found on our recommendations page here. They come in all different sizes so search for the ones that best fit your shelves.
You can buy growing kits complete with stands and lights w/o mats at Gardeners supply and on amazon but honestly, you will save a lot of money if you pick up used shelves from craigslist and buy lights and mats separately. Just be sure and check all the measurements so that they will hold your seedling trays well.
Lots of people here in Colorado ask me if they need a greenhouse and the short answer is probably not, but the long answer is heck, yeah you do! As I mentioned above, you can definitely make use of a spare room, basement or a warm sunroom if you have the shelving unit(s) I describe above. At the same time, a greenhouse is an incredible gift if you live in a climate with unpredictable weather in the spring/fall much less if you have long snowy winter months. Here are some of the reasons why I love mine and could never go back:
Equipped with shelves, lights, and mats a greenhouse takes all the guesswork out of growing everything from perennial/annual flowers to veg seedlings to propagating cuttings from berry bushes. Just be sure to plan for temperature fluctuations and have a temp sensitive heater for the winter and if possible fans/windows that open to alleviate summer heat. I mainly use mine in the fall, winter and spring so I don’t need the latter as much, but if you live in a climate where there are big temp fluctuations in the summer it is really handy to be able to open it all up to keep the temp regulated.
As soon as I started to grow more than a couple of seedling trays I quickly realized that I needed a lot of growing space for all my shelves, lights, and mats. In addition, I found that I needed to be incredibly organized. Every tray of starts needs to be dated and labeled at least twice so that plants don’t get mixed up (so frustrating) and having a place to keep all my tools, supplies and everything else in one place has been a godsend. Note: I don’t keep seeds in the greenhouse due to the temperature fluctuations. I keep mine in a dark, cool, and dry place to protect their longevity.
It is so wonderful to be outside when it’s too cold to work the ground. I heat mine enough to be comfortable and it provides a wonderful way for me to get Vitamin D during those long months when I would otherwise be indoors.
It is a safe place to move temperature-sensitive plants that can’t overwinter outside like citrus trees in pots, certain herbs, even annual flowers like geraniums which can come back if they are given enough light and warmth over the winter.
The dirt and water involved in growing plants stays outside my house. The base of our greenhouse is gravel and the entire growing area cleans up really quickly.
I have neighbors (you know who you are) who put the chem in Chem lawn. I really appreciate the ability to protect my seedlings from the chemical breezes that blow when people are using herbicides in the early spring months.
As always please email or reach out if you have further questions and remember if you are starting seeds this winter you might like working with soil-blocks. I wrote all about it here.