Growing Tomatoes in a Sunroom

by Eleanor
(Mississauga, Ontario Canada)

My sunroom only gets to 19 C during the winter. It faces West so it does get afternoon sun. I would like to be able to grow tomatoes in this room during the winter but I am having trouble germinating the seeds. In the summer it was fine.

I cannot afford the hydroponic route. But my husband is handy and I thought he could build me a fluorescent light stand that could be left on for 12 hours a day till the seedlings get up to 6" tall and then they could be transplanted, and put in the sunroom where they would get some sun.

Answer: Seeds do not require any light to germinate. What is needed is moisture and warmth. Most seeds (including tomato seeds) prefer a soil temperature of 75-80 degrees F, or 24-27 degrees C. The problem you are having with germinating your tomato seeds is likely due to cool soil temperatures.

Cool soil temperatures will cause your seeds to take twice as long to germinate and sprout. If temperatures dip even lower at night, the seeds may not sprout at all. You can help things along by placing a heat mat (also called a seed starting mat) under your seed-starting container. Placing an incandescent light bulb over the seeds may also provide enough additional heat.

Once sprouted, the tomato seedlings will require 18-24 hours of light in order to grow vegetatively. This can be from fluorescent light, natural sun light, or a combination of both. Once the plants have grown to the size you want, giving them 12 hours of un-interrupted darkness each night (at the same time each night) will cause them to go into flowering.

One thing you should be aware of is, with the cooler temperatures in your sunroom, your tomato plants will require less watering. Pay close attention to the moisture in the soil and make sure not to over-water. Over watering, especially in combination with cooler temperatures, can cause problems with stem rot, pythium, and powdery mildew.

Also, be sure to check out my page on growing tomatoes indoors, which has a lot of additional information you may find helpful. Good luck, and happy growing!

Click here to post comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Misc Hydroponic Gardening Q&A.

All of the items that I personally use and recommend!

AffordableGarden Design&Setup

(10 week update below)

Find out the cheapest and easiest ways to garden productively in this article.

Hi everyone, Jason from Jason's Indoor Guide here. When I got started with hydroponic gardening more than 24 years ago, my first garden used rockwool cubes and B.C. Nutrients....and I remember thinking to myself yeah, sure, there may be a lot of advantages to gardening with hydroponics, for example there are very few pest problems, therefore very little pest control, no weeding, no plowing or tilling the soil, no soil testing or having to add things into the garden soil, no watering the garden....but for someone who just wants to grow their own vegetables and have more control over their food supply and the quality of the food that they eat, the cost of constantly having to buy grow media and hydroponic nutrients makes this an expensive hobby for most people...

Epic Nutrient Change

I suppose when you take into consideration how much money you save NOT having to buy food at the grocery store, it is surely cheaper to grow your own food hydroponically even with the cost of high quality nutrients. Nevertheless, I didn't have a whole lot of money to work with and I needed to make my efforts as affordable and effective as possible....and in the last 24 years I HAVE learned a thing or two!

As you browse through Jason's Indoor Guide, you will notice all of the systems that I use personally are homemade systems. As I got 3 or 4 years of experience under my belt, I quickly adopted a preference to standing water systems and systems that use expanded clay pellets or lava rock, because the media is re-usable and it eliminates a huge operating expense. So once a hydroponic system is built, garden maintenance is minimal- check and adjust the nutrient solution daily, and to change it completely every 2 weeks....and the biggest operating cost is the hydroponic nutrients. (and the electric bill, lol)...

Homemade Cloner

And, regarding the cost of the nutrients....I experimented for about 3 years with making different compost teas and nutrient teas, but there is still a lot of expense $$$ associated with making high quality nutrient kelp meal, liquid seaweed, rock dust, bat guano, un-Sulfured molasses, worm castings. You can eliminate a lot of this expense by becoming an expert at making high-quality colloidal humus compost, and use your properly made compost as the basis of your hydroponic nutrient solution.

Unfortunately, I have been gardening for over 24 years and I have only just recently mastered this difficult skill....and even then, only because I happened to find a very easy to follow, high quality technique and decided to follow the instructions to the letter. I produced more high quality compost in just one week than I was able to use in a whole year! If you can master the technique, I highly recommend it. It is one of the top 3 things you can do to increase the productivity of your food production efforts, while at the same time decreasing the amount of effort required to grow all of your own food, and decreasing the total cost of operating your food production system.

And when I say decrease operating costs, I mean decrease them to almost ZERO, especially if you are producing your own nutrients...

High Efficiency

The ultimate solution to eliminate the cost of your hydroponic nutrients: Imagine a hydroponic system that does not require you to buy any nutrients, does not require you to make your own compost, and does not require you to brew your own nutrient tea. Seriously! No cost and no effort as far as providing nutrients to your plants! Plus, at the end of the gardening cycle you harvest all of your garden vegetables, PLUS YOU HARVEST FISH from the system--->


Click Here to learn more!

This solution is aquaponics. If you are serious about producing all of your own food and being self-sufficient, this is the ultimate solution for reducing expenses (as much as possible), reducing the total amount of work required, and maximizing the productivity of your gardening efforts. I have been gardening for over 24 years, and it is the perfect food production solution in my opinion.

Produce garnden vegetables AND fish together. Eliminate fertilizer costs!

Besides mastering how to make high quality compost, learning aquaponics is one of the top 3 things you can do to increase your garden productivity, reduce your total costs, and reduce your total work. The product that I learned from is called Aquaponics4you. With all of my hydroponic gardening experience, the first time I came across the Aquaponics4you product I knew immediately that it was something very special! Place an aquaponics system outdoors and use the sun instead of grow lights, and you have reduced every garden expense to nearly ZERO!

The Same System/ 10 Weeks Later!

If you've found this site helpful at all, I would really appreciate it