Ah, every gardener’s dream: a garden full of lush tomato plants, properly trellised, glistening with ripe fruit. Piles of tomatoes in harvest baskets, jars of sauce stocked in the pantry, and fermented salsa on the counter.

In order for this dream to come true in September here in the northern hemisphere, the process begins months earlier in February.

Tomatoes are a staple food in many kitchens - tomato sauce, pizza sauce, salsa, tomato soup, and even as a flavoring for broth. Tomatoes are a surprising source of calories, and growing them builds self-sufficiency in your kitchen and pantry.

Tomatoes do well with organic regenerative gardening methods, which I will outline for you here in this article. You can grow tomatoes without digging up the soil, and they also thrive in containers. Other regenerative practices, like crop rotation, mulch, and cover crops are all great for tomatoes to thrive in your garden year after year. These regenerative methods also help the health of your soil and sequester carbon in your garden over time.

I’ll share my techniques for planting tomatoes from seed to harvest, and break down the steps in this guide.

1. Where to source tomato seeds
2. What varieties of tomatoes to plant for your growing zone
3. When to plant tomato seeds by zone
4. How to plant tomatoes: depth, spacing, and best practices
5. How many tomatoes you can plant in the space that you have
6. How to plant tomatoes in containers
7. When the tomatoes are ready for harvest
8. How regenerative gardening practices will improve your tomato yield

→ TL;DR: How to grow tomatoes from seed
‍When to sow tomatoes indoors? Plant tomatoes indoors under grow lights in March or April.
When to transplant tomatoes outside? Sow tomatoes outside after all risk of frost has passed.
‍How to plant tomatoes? Plant tomatoes at least 2 feet apart after last frost. Plant seeds 1 inch deep, or plant transplants up to the 1st leaf nodules.. Mulch around plants, and water and fertilize them regularly.
‍When to harvest tomatoes? Harvest tomatoes when they are blush-red in color for most varieties. Pick them regularly for continual production, harvest all fruit before first frost.

A tomato timeline (for northern hemisphere growers)

January-February: Before you grow tomatoes

1. Choose what types of tomato seeds to grow for your tastes and needs

Tomatoes come in so many different shapes, sizes, and colors that it can be overwhelming to know what kind of tomato seeds you should buy.

Here’s a rundown of the different types of tomatoes, and their uses in the kitchen. Below each type I’ll list out varieties that are best for different growing situations:

Cherry: Small round snacking tomatoes that are also great in salads

• Recommended for Indoor Growing: Gold Nugget Cherry
• Best for Containers: Patio Choice Yellow Bush Cherry Tomato; Litt’l Bites Cherry
• Best flavor: Sungold
• Best for Late Blight Resistance: Cornell - Matt’s Wild Cherry

Pear/Grape: Small pear/grape-shaped snacking tomatoes that are great in salads and work well in containers

• Recommended for Indoors or Containers: Elfin (Grape); Sprite (Grape)
• Special Interest: Grappoli d’Inverno , Piennolo Giallo, Piennolo Rosso all can be hung indoors and stored long-term fresh

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Paste/Plum: Oblong medium tomatoes that have less water content and are great for making sauces and salsas

• Best overall: San Marzano, the gold standard of paste tomatoes; Amish Paste is a fantastic alternative with extra large fruit
• Best for containers: Dwarf Almandine;
• Recommended for Cooler Climates: Andes;
• Best for short season: Fiaschetto di Manduria
• Great for Dry Climates: Pomodoro Pizzutello Di Paceco

Beefsteak/Slicing: Globe and heart-shaped tomatoes great for, well, slicing. Add to sandwiches, or serve with a sprinkle of salt and some mozzarella cheese and basil.

• Best classic: Brandywine
• Recommended for Indoors or Containers: Beaverlodge Slicer; Bush Beefsteak;
• Best for Short Seasons: Siletz
• Late Blight Resistant: Legend, Cornell - Mountain Magic (hybrid)

Determinate vs Indeterminate Tomato Varieties

Determinate tomatoes grow to a “pre-determined” height and usually produce a crop of tomatoes within a shorter time frame. Determinate tomatoes are best for containers and small gardens, or for those who want to have a shorter harvest window from their plants. They require less maintenance and pruning overall.

Indeterminate grow for an “undetermined” length of time and will keep growing in height until the season is over. These types of tomatoes can take up a lot of space, but will keep producing tomatoes until your first frost. You’ll need a tall trellising system to maintain these properly in addition to frequent check-ins for proper pruning.

Disease Resistant Tomato Varieties

Late Blight Resistant Varieties:
‍Mountain Magic (slicer), Jasper (cherry), Matt's Wild Cherry, Mountain Merit (slicer), Legend (slicer), Defiant PHR, Plum Regal, Crimson Crush

Early Blight Resistant: 
‍Mt. Fresh, Crimson Crush

Septoria Leaf Spot, Early Blight and Late Blight Resistant: 
Iron Lady

Fusarium and Verticillium Wilt Resistant: 
‍Sunny, Mt. Spring, Carolina Gold, Cherry Grande, Roma

Tobacco Mosaic Virus Resistant: 
‍Sun Start, Sunny

Nematode Resistant:
‍Sunny, Daybreak, Celebrity

Sources: Cornell, UMass Amherst, Kentucky State,RHS

2. Get your Seed Starting Gear Ready for your Tomato Seeds

Plan out how you will start your tomato seeds. Will you start them indoors under a grow light? Outside under cover? Or will you wait until danger of frost has passed and direct sow them outside?

Whichever method works best for you, make sure that all of your supplies are ready, clean, and available.

If you’re starting seeds indoors, you’ll need:

• Grow lights (LED Shop Lights work well for me)
• Shelving Unit
• Seed starting trays, lids, and drip trays (Epic Gardening 4-Cells are great for tomatoes)
• Seed starting soil (If you can, buy organic seed starting soil)
• Fan (prevents legginess and fungal issues)

If you’re starting seeds outdoors undercover, you’ll need:

• Table (optional)
• Seed starting trays, lids, and drip trays (Epic Gardening 4-Cells are great for tomatoes!)
• Seed starting soil (if you can, organic)

If you’re starting seeds outdoors after frost and direct sowing, you’ll need:

• A long growing season 🙂 (or fast maturing varieties)
• Healthy Broken Down Compost

3. Calculate how many pounds of tomatoes you’d like to harvest, or how many you can fit in the space that you have

→ Rule of Thumb:
‍The National Center for Home Food Preservation shares that you’ll need 5 pounds of plum tomatoes for every quart of tomato sauce you want to make.
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‍UMaryland Extension lists that you can expect around 10-15 lbs of tomatoes per plant, but of course this will vary based on variety and growing conditions.

If you want 1 quart of sauce per week canned up on your pantry shelf, you would need around 25 paste tomato plants.

Amount of tomatoes to plant for any length of row:

A standard measurement is that your tomato plants should be 2 ft apart, so you could plant 5 plants in a 10 foot row in your garden.

If you have a 50 ft row, 25 plants could fit into that space.

How far apart to plant tomatoes:

It’s best to plant tomatoes 2 feet apart.

Grow tomatoes in a bag or container:

According to the RHS, a 12 inch diameter grow bag is best for dwarf and determinate tomato plants, which would be a 5-7 gallon grow bag.

10-15 gallon grow bags are best for indeterminate tomato varieties.

If you have the space, I’d recommend the 15 gallon size. I’ve personally had a lot of luck with that size and indeterminate tomato plants in my garden the past few years.

March-April: Sow your Tomato Seeds Indoors

→ Personal Experience:
‍When I start tomato seeds indoors, I always start twice as many as I’ll need. For me, my goal is to transplant 25 tomato plants into our greenhouse. If I start 50 seedlings, I give myself room for some margin of error. I also am able to pick the best looking 25 plants of the bunch. I inevitably end up with extra that I find room for outside in growbags and interplant them in my rows.

I’d rather have more tomato plants than I need than too few for my growing goals.

Tips for if you’re starting tomato seeds indoors:

• I bury tomato seeds 1 inch into their seed starting trays. I find this helps the stem and roots to be more solidly in the soil.
• Keep the humidity domes on the seed trays until germination, then remove.
• At germination, run a small fan lightly for three 20-min intervals daily. This will prevent legginess and disease.
• Keep just one plant per cell
• Bottom water your tomato seedlings to prevent disease issues.
• When plants reach 6-7 inches tall, pot them up into bigger pots so they have room to grow.
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May-June: Transplant tomato seedlings outdoors

You’ll need to check your local weather around the time of the average last frost for your growing zone to know when to plant your tomato seedlings out into your garden. The last frost date for your garden will vary from year to year, so it’s hard to be specific.

During the time of my average last frost date, I look for a good stretch of weather where night temperatures are at 38 degrees or higher before I plant out my tomato starts.

Tomato planting dates based on average last frost dates

Zone 2: Plant out around June 1
Zone 3: Plant out around May 25
Zone 4: Plant out around May 15
Zone 5: Plant out around May 15
Zone 6: Plant out around May 15
Zone 7: Plant out around April 15
Zone 8: Plant out around April 15
Zone 9: Plant out around April 1
Zone 10: Plant out around March 21

Steps for transplanting your tomato seedlings

1. Prepare tomato seedling: Remove the bottom leaves of the tomato seedling if the rest of the plant looks strong
2. Bury the tomato seedling up to the point of their first leaf nodules. If you removed the leaves, let the soil cover that point. If you didn’t remove the leaves, plant the tomatoes so that they are as deep as they can be without those leaves touching the ground.
3. Fertilize: In the planting hole, add in a good quality balanced organic fertilizer that also contains magnesium and calcium for best results. Espoma Tomato Tone or Organic Plant Magic Soluble Plant Food are two great options.
4. Optional mycorrhizomes: Add in a mycorrhizal inoculant. This year I noticed extra large fruit on the tomato plants that got mycorrhizal inoculant when I transplanted them. I used Trifecta Myco Supreme, but there are a lot of different brands out there.
5. Spacing: Space transplants at least 2 feet apart.
6. Water in: Water your transplant in well. Be sure not to get the leaves wet. Use drip irrigation or water at soil level.
7. Mulch your tomato seedlings: Mulch around your tomato plants with either dried out grass clippings or organic straw. If you’re planting tomatoes in a greenhouse, you’ll want a thin layer of mulch, around 1 inch. If you’re planting your tomatoes outside, you can add 2-4 inches of mulch if you have it available. This will prevent blight in the soil from splashing up on the leaves and help with water retention.
8. Hold water for a few days: A recommendation that I follow from Huw Richards is to hold off on watering my tomatoes after your initial watering for 6 or so days. This helps the tomatoes to develop deep root systems. Monitor your tomatoes and water them sooner if they start to look stressed.
9. Then, water at regular intervals: From there, water your tomatoes at regular intervals. This will help prevent blossom end rot. I like to run drip irrigation 2 times per week, with extra watering during extreme heat if necessary.
10. Support structures for your tomatoes: Install a trellising or support system to keep your tomatoes from falling over as they grow. Short stakes work well for determinate tomato varieties, but taller systems are necessary for indeterminate varieties.
11. Monthly fertilizing schedule: Feed your tomato plants with organic fertilizer or plant food once a month throughout the growing season.
12. Pruning schedule: Two-three times a week, check your indeterminate plants for suckers and prune them off.

How to direct sow tomatoes:

If you live in an area with a longer growing season or have greenhouse or row cover, you can also direct sow your tomato seeds instead of starting them indoors.

1. Timing: You’ll need to wait until all chance of frost has passed. Reference the transplant dates above for when to sow your tomato seeds.
2. Sowing: Sow your tomato seeds around 1 inch in the ground, at least 2 feet apart. Keep the area well watered until germination occurs.
3. Watering: Once germination occurs, be sure to water only through drip irrigation or at the surface level. Overhead watering can cause disease issues in your tomato plants. Water your tomatoes at regular intervals 2-3 times a week.
4. Mulch: Mulch lightly around your tomato seedlings once they sprout. Weed-free non-sprayed dried grass clippings work well for this, as the darker color of the grass will help keep the soil warm and moist. As the weather warms up, you may wish to add organic straw mulch to help keep soil temperatures cool.
5. Fertilize: As the tomatoes start to grow, feed them with Espoma Tomato Tone or Organic Plant Magic monthly. You may also wish to add in a mycorrhizal inoculant for larger fruit production.
6. Support structure: Add a trellis or support structure so that the tomato plants do not topple over as they mature.
7. Pruning: For indeterminate varieties, prune suckers 2-3 times a week to be sure that the plant is reserving as much energy as possible for fruit production.

How to grow tomatoes in containers:

For the most part, the guidelines for transplanting tomato seedlings and sowing tomato seeds directly apply to tomatoes.

Here’s some guidance on how many plants to grow in your containers:

• 5-15 gallons: Plant 1 determinate variety in each pot
• 10-15 gallons: Plant 1 indeterminate variety in each 10-15 gallon pot
• 25-35 gallon grow bags: You can plant 2 tomato plants. Be sure to install a support system for plants and keep them well pruned for optimal air flow.
• 45-60 gallon grow bags: You can plant 3-4 tomato plants. Be sure to install support structures and stay on top of pruning.

July-August: Tomato Tending

• Continue to water your plants at regular intervals with extra water during times of extreme heat.
• Add organic fertilizer or plant food to your tomato plants once per month.
• Prune suckers off your indeterminate plants 2-3 times a week.

September-October: Tomato Harvest

Tips on harvesting tomatoes:

• I freeze my paste tomatoes as I bring them in and then I make sauce to preserve all at once. I learned this tip from Acre Homestead - thanks Becky!
• If you're fighting blossom end rot, try to harvest tomatoes when they are in their blush stage. Let them finish ripening inside.
• Harvest all tomatoes before your first frost.
• Bring in green tomatoes and let them finish ripening on the vine. Ensure good air circulation to prevent tomatoes from going bad.

October-November: Clean Up and Cover Crop

Since tomatoes can host so many different diseases and pests, it's important to clean up all of your tomato plant debris once the season is complete. Tomatoes are one of the few vegetables that I pull up the roots of the plant in order to prevent disease spread.

Once your area is fully cleaned up, plant a cover crop of hairy vetch to support the health of the soil, boost carbon sequestration, and prevent future disease issues.

Regenerative gardening techniques for growing tomatoes from seed

Interplanting/Companion Planting with Tomatoes

Interplanting tomato plants with other non-nightshade vegetables or an assortment of herbs and flowers is a regenerative practice. The more diversity and variety in your garden, the more biodiversity you’re building in the soil microbiome.

Herbs and flowers also bring in beneficial insects, which can support your tomatoes by eating potential pests.

There are certain companion plants that are scientifically proven to help tomato health and vigor.

French Marigolds and Tomatoes as Companion Plants:French marigolds have been shown to support tomatoes in two ways.

In 2019, a study out of the UK showed that French marigolds helped reduce whitefly damage on greenhouse grown tomatoes. According to the study, this technique works best at the start of the season, before the whitefly population becomes an issue.

Additionally, in 2007 a study from the University of Hawai’i showed that marigolds protected tomatoes from root knot nematode. They also share that in California, marigolds helps reduce root-knot nematode over seasons. In turn, the tomato harvest increased by 50%!

Basil and Tomatoes as Companion Plants:

Basil and tomatoes are a classic companion plant combination that actually has scientific backing from several studies.

In 2020, a study found that growing tomatoes and basil together in a 1:1 density increased the growth of the tomato plants.

This finding was confirmed in 2022, when a study from Hungary found that tomato and basil interplanting increased the size of the tomato plants and their harvest. Basil also helped tomatoes to have less disease, specifically less fusarium wilt.

In 2016, a student paper from Rappahannock Community College found that basil as a companion plant supported tomatoes in yielding more fruit. This paper noted that roots were also bigger and deeper. What’s fascinating is that in this study, tomato plants grown with basil and no fertilizer performed the same as tomato plants grown with fertilizer.

Mulch tomato plants

Regenerative agriculture advocates mulching your garden for many reasons. Mulch adds organic matter to the soil, prevents soil erosion, and helps maintain soil moisture. When the soil is covered, the soil microbial community is able to thrive because the soil won’t get dried out and the mulch provides food for microbes to eat.

Mulch has been shown to protect tomatoes from any blight spores present in the soil.

Common materials to mulch your tomatoes with are weed-free herbicide-free grass clippings, and organic straw.

Add compost to tomatoes

Add compost to the tomatoes when you plant them to increase soil organic matter levels. Compost also helps balance out the structure of both clay and sandy soils.

Compost supports your garden and the environment in a number of ways. According to the EPA, compost adds biodiversity to the soil microbiome, and reduces the amount of watering needed for your crops. Compost reduces soil erosion and helps sequester carbon in the soil.

The EPA shares that compost can reduce the need for chemical inputs, such as fertilizers and pesticides.

Compost does all of that while also increasing plant vigor and harvests.

Encourage pollinators

Regenerative farming understands the importance of plant diversity, including native flowers and herbs.

These plants are beautiful and fragrant, and bring in insects that offer the important ecosystem service of pollination.

Be sure to encourage pollinators in your garden to help tomatoes to set fruit and produce an improved yield.

No-till tomato growing

No-till garden practices preserve soil structure, moisture, and microbial activity. This can enhance tomato fruit development, nutrient uptake, and water retention. All together, the yield and health of your tomato plants is improved.

When soil is tilled, it releases its sequestered back into the atmosphere.

There is an alternative to tillage. In compacted soil, use a broadfork to loosen the soil. This has worked great for my garden in the past.

Crop rotation

Crop rotation is a regenerative gardening practice that reduces pest and disease issues. Studies show that a 3-4 year break from certain plant families makes for healthier crops. Crop rotation avoids a lot of disease and pest issues.

Tomatoes are part of the nightshade family. Be sure not to plant it in areas where other nightshades have been recently planted. These other nightshade plants include:

• potatoes
• eggplant
• peppers
• tomatillos

Water conservation

Mulch and drip irrigation are two ways to conserve water in your regenerative garden.

We’ve talked about the merits of mulching throughout this article, but it bears repeating that mulch is pretty fantastic for your garden as a whole.

Drip irrigation is another important way to save water in your garden. In fact, UMass Amherst notes that you use around 80% less water when you have drip irrigation correctly in place.

Organic practices

Regenerative gardening focuses on healthy soil, healthy food, and a healthy planet. This means no synthetic pesticides or herbicides.

Synthetic inputs create soil that is void of the normal microbe-plant relationships. These chemicals are also made from petroleum products. Overall, synthetic inputs add greenhouse gases into the environment.

Cover Cropping After Growing Tomatoes

Your tomatoes will be harvested from August-October in the northern hemisphere. Once the crop is done, there’s one more step to take to nourish the soil: cover cropping.

Regenerative gardening looks to maximize photosynthesis to store carbon in the soil. You can do this with a cover crop, sown after the tomatoes are harvested.

Look for varieties of cover crop that do well when sown in cooler weather. Daikon radish can be a great choice if you noticed that your soil was compacted. Hairy vetch is a fantastic winter-sown cover crop that is shown to prevent blight in tomatoes. You can also plant a mix of daikon with hairy vetch to get the best of both worlds.

Common tomato problems

Avoid overwatering or waterlogged conditions that can lead to rot. Practice crop rotation and maintain good garden hygiene to prevent disease recurrence.

Heavy rainfall or extreme temperatures may also affect tomato growth.

To manage pests and diseases in tomatoes, it's important to be proactive.

Common tomato pests include whiteflies, tomato hornworm, root knot nematodes, and thrips.

Be observant of your tomato plants and pick off any pests that you see. A solution of soapy water applied with a spray bottle can help too.

Of course, crop rotation is another effective way to reduce the incidence of pests and disease in your garden.

Proper trellising, pruning, and air flow help to reduce disease in tomatoes. Be sure to never water your tomatoes overhead, which will also help reduce incidence of disease. Remove lower leaves if they start to touch the soil. Mulch around your tomatoes to prevent blight splash-up.

If you have had blight in the past, try to grow a blight-resistant tomato variety and be sure to rotate your nightshade plants.

What's next?

Learn about how regenerative agriculture sequesters carbon and benefits the environment here.

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