How to Grow Roma Tomatoes in Pot
We wanted to give our readers access to what it’s like to grow a Roma tomato plant for a full growing season and for it to be a lesson on How To Grow Roma tomatoes from seed. Therefore, this year, you can follow along with us as we grow the Classic Roma, OG, (Organically Grown) in a 5-gallon container.
Disclaimer: The following How To is just one way to grow a Roma tomato plant. There are many different methods, tips, and dos and don’ts on growing tomatoes. The following method is right for our climate zone, requirements, and situation. We hope that it will be helpful to readers. Also, tomatoes grown in containers larger than 5 gallons, (10 to 25 gallons) will produce more and larger fruit, but 5 gallons is what we have to work with this year. So,…
Classic Roma OG (Organic Grown) tomato seeds by Burpee, purchased from a local hardware chain. Tomato seeds need to be started indoors, for 6 to 8 weeks before they are transplanted outside. This should be done between Valentine’s Day and St. Patrick’s Day, depending on where you live.
Peat Pellets for Starting The Best Way to Grow Roma Tomatoes from Seeds
The one on the left is dry & compressed as it comes from the supplier. The one on the right has been hydrated with water and is full-size.
Hydrated peat pellets inside their starter tray. Seeds (which can be seen in the top two) are planted about 1/4″ to 1/2″ deep, then covered. I use the tip of my pocket knife to pull the peat apart to make a hole, and to push the peat back into the hole, to cover the seed.
Planted peat pellets are placed inside a WindowSill Greenhouse starter tray. Larger trays are available. We use the small one here for demonstration purposes.
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The pellets are watered and the greenhouse lid is placed on top and the starter tray is set in a window that receives the most Sunlight. The water inside the tray evaporates and collects as condensation on the inside lid. This provides moisture and a sort of humidity with warm temperatures that help foster germination.
The starter trays with the greenhouse effect are a great way to start Roma Tomatoes indoors. We get a 96 percent germination rate using this method. Starter trays and peat pellets can be purchased from any garden supply or hardware store that offers a garden section.
We Planted Our Roma Tomatoes and Spitze Tomatoes
Tomato sprouts in peat pellets. As you can see, they are quite tall. I let them grow a little bit too tall so I can plant them DEEP!
Roma Tomato Sprout transplanted to 5-inch pot. Plant your sprouts deep, really deep, so that they can develop a robust root system and grow more vigorously.
Place tomato pots in front of a Sunny window for 6-12 hours of sun a day. If you don’t have enough Sunlight or have too many plants for your window, consider getting a grow light (info below)
In about 7-10 days, your seeds will start to sprout in their peat pellets. In 7 to 10 more days after that, they will be ready to transplant into 3 or 4-inch peat pots as they outgrow their pellets and starter trays. Most paste tomato growers use 4-inch peat pots, and so do we, but our local supplier ran out much earlier than we expected (unexpected jump in gardening this year I assume) and so we were only able to get 3-inch pots and use some empty plastic containers we had the foresight to save.
Read More: Growing Hanging Tomatoes Method
Prepare your Container Soil to Grow Roma Tomato
Here in our part of Oklahoma (Tulsa), the soil is atrociously bad. Clay, sandy, full of sedimentary rocks and other pebbles – it’s about useless for a garden in many areas, but not all. Therefore, we have to buy our soil and compost. (We started our own compost pile but it won’t be ready for another year or so). We buy high-quality compost from a local supplier by the pickup load and then buy bagged regular topsoil and mixed garden soil (compost & rich soil mixed together).
We also buy a bag or two of peat moss. For the pots, we put about 2/3rds of mixed garden soil in a 5-gallon bucket and 1/3 compost and mix it up well. We then use that 5-gallon bucket of soil to supply our 3″ and 4″ pots. As we transplant the seedlings into the pots, it’s important to plant it as deep as possible. You want to get that stem down deep so more roots can sprout and shoot off, giving the plant a sturdy and strong base.
Sun & Artificial Light
In our part of Oklahoma, we get enough Sunlight during February, March, and April to keep our paste tomato plants in front of a window all day long and do the job well. Tomatoes NEED lots of Sun at this point. The more the better. However, in northern Climates, there just may not be enough Sunlight to do the job.
Paste tomato growers in those colder, Northern states have to resort to vegetable growing lights. There is a whole science and school of thought on what kind of lights to use, how much, how big, and how long. But since we don’t use them, yet, we’re not experts.
If you live in a colder climate and don’t have a greenhouse, the folks at gardensnursery.com can guide you on the type and size of grow light you need, as well as for instructions for using them. As the size of our garden grows, along with the number of vegetables we start in February and March, we might have to get a grow light if we run out of window space. Maybe next year.
Special Note: If your Roma tomatoes are too leggy and low on foliage/leaves, this means they are not getting enough Sun. Get more sunlight on them or use a grow light. It is possible to turn this problem around.
Hardening off your Roma Tomato Plants
All tomato plants started indoors (and not in a greenhouse) need to adjust slowly to outside temperatures and breezes before transplanting (picture at left, above). This is called “hardening off.”
This is done mid to late April. On Sunny, breezy days, leave your tomato pots outside in the Sun. Keep an eye on it so it doesn’t wilt or get damaged by the wind. If it’s too breezy, use a windbreak or take the plant back inside, and let it get Sun and breeze from an open window.
How to Grow Roma Tomatoes in a Raised Garden Bed
At right, above, we’ve transplanted our 6.5 weeks-old Roma tomatoes to a 5-gallon bucket. (A raised bed garden would be better, but we’ll be moving from this starter home to a larger house/acreage as our family grows. Therefore, why invest some money in a big, raised bed garden?) For Romas, a 5-gallon container will do fine as these are determinate plants that are shorter and bushier.
Prior to transplanting, we sprinkled some tomato food granules into the hole we dug. Water afterward. If temperatures dip to the 40s or lower at night, cover young plants with cloth, a smaller plastic pail, or any unique cover sold in garden centers.
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