How to Plant Tomatoes in Gardens & Containers
How to Plant Tomatoes in Gardens & Containers
Tomatoes are one of the most rewarding crops to grow, but getting them off to a strong start makes all the difference in how they perform the rest of the season. Whether you’re tucking one into a patio pot or filling up garden beds, this guide walks you through exactly how to plant tomatoes outdoors the right way.
This guide focuses on transplanting tomato seedlings—whether you’ve purchased them from a nursery or started them from seed indoors. If you’re looking to grow your tomatoes indoors or outside from seeds, check out my post on growing tomatoes from seed for everything you need to know before planting day.
When to Plant Tomatoes
Timing matters—maybe more than you’d expect.
Tomatoes are warm-weather plants that HATE the cold. Whether you’re planting in the ground or in containers, wait until all danger of frost has passed and nighttime temperatures are reliably above 50°F. In most areas, that’s a couple weeks after your average last frost date.
Also, make sure your soil temperature is at least 60°F. Tomatoes just won’t thrive in cold soil. You can check this with a soil thermometer if you’re unsure.
If you plant too early, tomatoes won’t grow faster – they’ll just sit there looking grumpy (and possibly get damaged).
If you’re not sure when your last frost date is, you can look it up by ZIP code using a frost date calculator.
Choosing a Tomato Variety
Not all tomatoes are created equal when it comes to planting success. Some do better in pots, others love to sprawl in raised beds or traditional gardens. Before you buy your plants, take a minute to match your space and goals to a variety that fits.
Need help deciding? Check out my guide to tomato varieties for all the details on indeterminate vs. determinate, best types for containers, and which ones are best for eating, cooking, canning, etc.
Harden Off to Start
Whether you started your tomato plants indoors or bought seedlings from a greenhouse, they’ve been living a cushy, climate-controlled life. Suddenly tossing them outside into sun, wind, and cool nights is a shock they don’t handle well.
To toughen them up, you’ll want to harden them off, which just means gradually introducing them to outdoor conditions over the course of about 7–10 days. Start by putting them outside for a couple hours in a shady, protected spot. Add more time and more direct sun each day until they can handle a full day outside without wilting or stressing out. By the end, they should be ready for the real world (and real soil).
This small step makes a big difference in how well your tomatoes adjust after planting.
Where to Plant
In the ground: Pick a spot with full sun (at least 6–8 hours a day) and well-draining soil. Tomatoes like slightly acidic soil (around pH 6.0–6.8) that’s rich in organic matter. For heavy or compacted soils, consider planting in raised beds or mounds to improve drainage and keep roots healthier.
In containers: Choose a sturdy pot with drainage holes. For determinate varieties, aim for a 5-gallon container. For indeterminate types, bigger is better—10 to 20 gallons if you have the space. Clean and disinfect reused containers to avoid transferring diseases from previous seasons. (Check out the complete guide to growing tomatoes in containers for more tips.)
Preparing the Soil
- For beds or raised gardens: Mix in compost or aged manure before planting. If your soil is heavy, loosen it up and add organic material for better drainage. (Here’s how to find out your soil type.)
- For pots: Use a high-quality potting mix (not garden soil). Bonus points for adding compost or worm castings to the mix.
How to Plant Tomatoes (Step by Step)
- Remove lower leaves from the seedling—you’ll bury part of the stem.
- Dig a deep hole or trench. For leggy seedlings, you can plant at an angle in a shallow trench, leaving just the top few inches above the soil. This helps support weak stems and encourages a stronger root system since the tomato will put out more roots from its stem over time.
- Add a scoop of compost or a slow-release fertilizer to the planting hole. It can also help to mix in a bit of bone meal or a fertilizer with calcium to help prevent blossom end rot later on.
- (Optional) Water the hole with a diluted starter fertilizer or root stimulator before planting. This can reduce transplant shock and help roots get settled faster.
- Set the plant in the hole and gently fill in around it with soil. Press the soil down lightly to get rid of air pockets.
- Water deeply. You can water in stages—let the water soak in, then water again—to make sure it gets deep into the root zone.
- Add mulch around the base to retain moisture and regulate soil temperature. (Here’s how to mulch).
- Plant in the evening or on a cloudy day if possible. This reduces transplant shock and gives the plant time to adjust before the sun hits it full blast.
- Space plants properly if you’re planting in a garden in rows. For determinate types, give them 24–36″ between plants. Indeterminate varieties need more room—36–48″ between plants and 3–4 feet between rows for good airflow and disease prevention.
- Avoid planting in the same spot each year. Rotating your tomato crops annually helps reduce disease risk, especially if other nightshades like peppers, eggplants, or potatoes were planted there last season.
Additional Tips for Pots and Gardens
- One plant per pot —no exceptions. Even in large containers, tomatoes compete for nutrients and water.
- Group plants together (while still following spacing requirements) to help shade roots and make watering easier.
- Stake or cage right after planting so you don’t damage roots later.
- In hot climates, provide some afternoon shade to avoid sunscald and blossom drop.
- For early plantings, use row covers or hot caps to protect young plants from late cold snaps.
FAQ About How to Plant Tomatoes
If you live in a cooler climate, starting seeds inside gives tomatoes the head start they need so you’re not waiting until August for that first red one to ripen. Tomato seeds need warm soil to germinate—ideally between 70–85°F—which is hard to get outdoors in early spring. Plus, seeds can take 5–10 days to sprout, and cool soil will slow them down even more.
The best way is to plant them deep—either straight down or sideways in a trench—so that much of the stem is buried. This allows roots to grow all along the buried stem, giving your tomato plant a stronger start. Be sure to water deeply, add mulch, and space them correctly based on the variety.
Compost or aged manure is a great start. You can also add a slow-release fertilizer or bone meal (a calcium source), and even water the hole with a diluted starter solution to reduce transplant shock.
Plant after frost, bury the stem deep, leave space between plants, use nutrient-rich soil, water well, and give them full sun. Don’t plant them in the same spot as last year’s tomatoes or other nightshades.
Happy Growing!
Planting tomatoes is pretty straightforward once you know the basics, and doing it right sets your plants up for good growth and an awesome harvest. Whether you’re growing in containers or in garden beds, give them warmth, sunlight, and support from the beginning.
Planting is really just the start of your tomato adventures! To learn more, I have a complete tomato care guide, along with lots more on…
