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Check out this handy guide to learn how to Transplant Tomatoes into a Greenhouse!
Why Should I Be Transplanting Tomato Plants?
To put it most simply, planting tomatoes in a greenhouse extends their growing season. Most popular greenhouse setups allow for things like temperature control, more control over the irrigation system, and ability to monitor things like air circulation and humidity level.
Growing tomatoes in a controlled environment will allow you to tend to them outside of their natural growing season in your climate. It can also prevent disease and infection ensure you end up with the healthiest tomato fruits possible! But there are some things to consider for growers of tomato transplants, so let’s get into it.
Want read about how to build a greenhouse for your back yard?
Our Tomato Plants
Because of our cooler nights, we start many of our vegetables inside the house. Right now, I have beans, corn and zucchini busting out all over the living room.
We have much better luck transplanting rather than direct seeding any of the heat loving vegetables that we grow.
Our elevation means cooler temperatures and so we get them started early inside and pop them into the garden towards the end of May.
Although I would love to be doing that this weekend, it is still just too cold out there. What happened to all that sunshine and heat we were having just a week or two ago?
It’s not stopping me though; I’ve just moved into the Greenhouse. I spent some time cleaning it out and then started watering it. It takes several days of good watering to moisten the soil enough to transplant tomatoes into a greenhouse.
My tomatoes are getting a bit leggy although they do have nice thick stems for their size. If I don’t get them planted in the greenhouse I would have to transplant them into even larger pots.
Transplanting Tomatoes into Larger Pots
Most years, I have to transplant tomato seedlings from their starter pots into larger pots. You can read about why it is important to do that; it is especially important for people living with short growing seasons.
My tomato trusses all in place. You can see I just go out in the bush and saw off some limbs to use as stakes. What are the black jugs for?
I’ve got some fantastic hand garden tools this year – a serrated trowel and a 3 tine cultivator from De Wit Garden Tools.
I am looking forward to using these quality tools for many years to come.
Once the greenhouse soil is nice and moist, I pound the tomato stakes into the soil, spacing the stakes as needed so the plants have room to grow.
I’ve got three different kinds of greenhouse tomatoes this year planted and later I’ll be adding my pepper plant seedlings alongside.
How to Transplant a Tomato Plant
Here are some general tips on how to replant a tomato plant:
Choose a spot in the greenhouse that gets lots of sunlight. If possible, check the soil to ensure it’s rich in nutrients like nitrogen, calcium, magnesium, and potassium, or enrich it with soil or potting mix. Also, you can use a PH test kit like this one, to check that pH levels are optimal–you don’t want the soil to be too acidic.
When I transplant tomatoes I always remove the bottom set of leaves and tend to any side shoots that grow off the main stem. Then I plant deep into the hole so more of the stem is covered.
If you like, you can also use organic fertilizer, compost, manure, or another nutrient-rich growing medium to further promote growth. Apply the fertilizer at the time of transplanting, and then once more just before fruiting if you like.
This will help the plants grow strong with sturdy stems to support the weight of the tomatoes. Velcro ties are used and these will be checked and adjusted as the season goes on.
Watering Transplanted Tomatoes
When transplanting tomatoes, I create a well around the plant to hold onto the water. For the next several days I will keep them well watered to help them settle in. After they’re settled, tomatoes typically don’t need huge amounts of water. Overwatering can actually be harmful for them, so be mindful of water application to prevent disease and other harm from affecting your plants.
For the rest of the season I will be checking the Greenhouse every day – if it needs watering, it will get it. The hotter the days become, watering every day is a must – we may even set up a drip sprinkler on a timer in here.
Note: When watering tomatoes, try to not get the leaves wet! This is why soaker hoses or drip sprinklers work well in a greenhouse.
In a few months, it should be looking more like this and we can’t wait. Harvests are a highlight of the summer when we can pick and eat these right off the vine and have baskets of delicious tomatoes!
What is the Best Way to Transplant Tomatoes?
A simple answer to this is to plant the tomato in good soil, remove the lower side shoots and then bury the stem as deep as possible. This will enable roots to grow laterally from the stem. You need to ensure that your tomatoes are able to take hold of their new environment, and the best way to do that is give the stem and roots lots of opportunity.
What Tomato Variety is Best for a Greenhouse?
When picking out your tomato seeds or tomato seedlings, it’s important to consider your climate and the type of tomato. There are two major kinds: determinate tomatoes (bush tomatoes) and indeterminate tomatoes (or cordon tomatoes).
In most cases, you’ll probably want to go for indeterminate varieties if the climate allows it, as this variety continues to grow throughout the growing season and continually grows fruit throughout the entire season. They’re also called vining tomatoes.
Types of Indeterminate Tomatoes
- Beefsteak
- Big Boy
- Brandywine
- Sungold
- Sweet Million
- Early Girl (one of our favorites)
- Gardener’s Delight
Types of Determinate Tomatoes
When is a Good Time to Plant Tomatoes?
This may require some planning, but you’ll want to sow tomatoes seeds indoors in January or so, then transplant to your greenhouse in April or May. Depending on the climate, you may even be able to move the tomatoes as early as late February or early March. Pay attention to the last frost date in your area–past this point, you’ll be able to transplant tomatoes into a greenhouse.
How to Prevent Pests from Ruining Your Tomatoes
There are a number of insects and other animals that could pose a threat to your tomatoes. Aphids, flea beetles, whiteflies, cutworms, and nematodes are all possible, though aphids and whiteflies are the most common.
For the most part, removing infected parts of the tomato plant is often enough to stop the pests. In extreme cases, you may have to resort to sticky traps or pesticides. We don’t use pesticides here, so we only use natural ways to get rid of pests.
Generally, keeping a good eye on your plants and taking good care of them is a great way to shore them up against pests.
How to Ensure Proper Pollination of Tomatoes in a Greenhouse
You’ll also want to make sure that bees are able to access your plants for pollination. Bees are the opposite of pests! But in some greenhouses, this won’t be possible. Especially if you don’t have a lot of good natural airflow.
One way to distribute the pollen yourself to ensure proper fruiting is to use tools like electric toothbrushes or other kinds of electric vibrators to spread the pollen. For only a few tomato plants, you can also be more precise with a cotton swab or small brush.
More articles about growing Tomatoes
Read here to find out how to ripen green tomatoes indoors fast!
Want to make your own home made Tomato sauce? Here’s my recipe! Canning instructions included too!
Now that you know how to transplant tomatoes into a greenhouse, grow some tomatoes this year!
Originally published 2016; latest update November 2022