Grow Striped Stuffer beefsteak tomatoes from seeds

We grow Striped Stuffer beefsteak tomatoes every year! This versatile fruit has a great taste and gives a plentiful harvest throughout the season.

Good to eat on their own, chopped up in salads, to stuff with fillings, or cook in the oven or on the barbecue. 

UPDATE 1: Photo above was taken late May and shows beefsteak tomatoes starting to form on one of our tomato plants started from seed in February this year. Striped Stuffer (Solanum lycopersicum) is one of the more popular beefsteak tomatoes to grow at home. We show you how to easily start growing your own beefsteak tomatoes from seed.
UPDATE 2: See below for photo of three beautifully red Striped Stuffer beefsteak tomatoes taken 7 July.
Beautifully ripening Stuffed Striper beefsteak tomatoes (photo taken 7 July)
Ripening beefsteak tomatoes on the vine (taken 7 July)

Why we grow beefsteak tomatoes

Tomatoes are a staple in many fruit and vegetable gardens. And there are numerous varieties to choose between, coming in all different shapes and sizes. 

Cherry tomatoes are for example a perfect snack or green salad ingredient with its bright and fruity flavors. And this is true for many varieties of tomatoes that are eaten fresh during a summer growing season where the natural sun sweetens the taste and aroma.

This is also true for Beefsteak tomatoes like the Striped Stuffer. Beefsteaks can of course be eaten fresh, such as thinly sliced and served with mozzarella cheese and olive oil or capers. Or why not a tapenade made from olives or a salsa verde. 

Ripening striped stuffer beefsteak tomatoes started from seed
Beefsteak tomatoes ripening on the vine (taken 3 July)

But beefsteaks really shine when cooked to allow the sweetness of the tomato to mix with whatever filling or sauce you have prepared.

And this – for us – is why beefsteaks are a must to grow in any garden.

What you need to start beefsteak tomatoes from seed

Watch this video on YouTube.
Short video with step by step instructions on how to start beefsteak tomatoes from seeds

Beefsteaks can be grown in pretty much any grow bag, pot or container. But when you pay attention to a few basic details you will be rewarded with a richer harvest that extends for the entire growing season.

1. Start with quality seeds 

Quality does make a difference when it comes to the seeds you plant.

And do not confuse quality with expensive.

Rather, quality refers to how the seeds have been stored, handled and ultimately produced. 

If you buy your seeds from your local garden center you should be fine. 

But if you for some reason decide to use the leftover seeds from last year or seeds from an unknown source – do yourself a favor and pre germinate the seeds.

This additional step is a great way to use up old seeds whilst making sure you only plant viable seeds that germinate.

We always have seeds leftover from the previous year. And we never throw away seeds. So yes, we pre germinate lots of seeds every season.

2. Use a good quality potting soil mix

These days there are many popular seed starter mixes that are in fact soilless.

We favor either hydroponics or using a soil based potting mix. We do on occasion mix different types of soil but for our tomatoes we use a lean potting mix with added Perlite. 

We do not add a lot of Perlite, usually between 5-10 percent. Perlite helps the potting mix drain while retaining a good level of moisture.

You want the potting mix to be moist but not wet. Perlite is helpful on those occasions when it is easy to water a bit too freely.

3. A pot that helps with moisture control

Use pots or seed starter systems that are suited for helping you control the level of moisture.

We grow most herbs in plastic starter pots and use plastic wrap to help retain moisture for seeds that are planted on the surface like basil, Thai basil, thyme and oregano.

Plastic starter pots also work for other herbs including sage, coriander/cilantro, arugula/rocket and other lettuces and leafy greens.

But when it comes to tomatoes we prefer to use seed starter trays with plastic domes.

Why? Well, it’s really a matter of convenience.

Seed starter trays with domes help with moisture and temperature control and are easy to move around as needed. And for tomatoes – as well as chillies and peppers – we have learnt that controlling these two factors lead to a high germination rate and strong seedlings. 

4. Provide plenty of light and warmth

When you start seeds indoors early in the year you become responsible for light and temperature.

Waiting just a few more months and mother nature will provide both for free. But when planting early it does become your responsibility.

It is important that you understand that light and warmth are two different things.

A lamp generating a lot of heat is not the solution.

Instead you want a grow light that generates a lot of artificial light but no heat. In addition you want a heat mat or another source that generates heat from below. 

Yes, you want the potting soil mix to warm up. 

Do not worry if you do not have a heat mat. Placing pots on top of a refrigerator or another electrical appliance is a well known trick to give seeds that bit of extra heat that is needed for good germination. 
First leaves spouting from tomato seeds planted at home
First leaves sprouting calls for a slightly cooler temperature

When seeds germinate you are looking for a temperature between 22-25 Celsius / 72-77 Fahrenheit. As first leaves sprout you should scale back the temperature to 18-20 Celsius / 64-68 Fahrenheit to avoid seedlings growing leggy and spindly. 

But do not micromanage your pots. Avoid doing 10 small changes per day in anticipation of “something”. 

Place your pots in the best available environment.

Now observe and be a bit patient. Keep an eye on moisture levels and temperature over a couple of days.

If something is clearly not right, take immediate action. Otherwise, be patient and only make small changes as needed, if needed.

In a perfect world you plant your beefsteak tomato seeds, water once a day and nothing more. Be patient and trust the process.

If you find it hard to wait for the first leaves to sprout, you may want to try pre germinating your seeds using a paper towel. When you pre germinate your seeds you benefit from a more visual germination process and there is no need to wonder what goes on below the surface.

Start beefsteak tomatoes from seed – step by step

  1. Fill pots with potting soil mix that drains well
  2. Bottom water the pots by placing the pots in a water bath
  3. Remove pots from water bath when they have absorbed enough water (up to 15 minutes)
  4. Let the pots drain off any excess by leaving them on a flat surface for 5 minutes
  5. Place pots back in container that is now empties from water
  6. Use wooden stick or instrument to make holes for seeds in pots (2 per pot)
  7. Plant seeds using toothpick and water 
  8. Cover pots with thin layer of potting mix
  9. Spray soil with water
  10. Cover pots with plastic dome (plastic wrap) and place in warm and bright location 

Care for the germinating seeds as well as first and true leaves

Beefsteak tomato seeds take anything from 5-15 days to germinate depending on factors like temperature, potting soil mix, light and of course watering.

As seeds germinate and you see first leaves you should move your young plants or seedlings to a somewhat cooler growing environment. Aim for a temperature of 18-20 Celsius / 64-68 Fahrenheit for seedlings to grow strong and compact.

Conservatories and greenhouses get very hot even when there is a relatively low level of light (few hours and/or low intensity). Placing tomato or chili seedlings in a low light and high temperature growing environment will result in weak, spindly and leggy seedlings.

Keep seedlings watered and make sure to keep potting soil mix moist.

First transplant into separate pots

It is the tiny bumps and not the trichomes (hairs) that form new roots
When planted deep, new roots are formed from the tiny bumps (not the trichomes)

When you see four true leaves it is time to transplant the seedlings into separate pots measuring approximately 10 cm / 4 inches. 

Take care to plant the young seedling deeper than it was growing. The seedling will grow new roots from the stem and planting the seedling deeper will give you a stronger plant.

Fill pots with a standard vegetable garden soil as the young plant needs nutrients to grow.

There is however no need to feed the young plants liquid nutrients at this stage.

But make sure to give plenty of water and light to help roots get established and new roots to form.

The new roots do not grow from the fuzzy hairs, or trichomes, that you see along the stem of the tomato plant. But if you look even closer you will also see small bumps along the stem. And these small bumps are were the new roots will form when tomato seedlings are planted deep.

Beefsteaks can be strong growers

Beefsteak tomatoes like the “Striped Stuffer” grow into large plants. 

This is also why you, as your young plant develops, may need to transplant the growing tomato plant one more time. Choose a pot measuring 20 cm / 8 inches across and top up with fresh soil as needed.

Continue to give plenty of water and light.

Prepare to move tomato plants outdoors 

When there is no longer any risk of frost, it is time to move the developing tomato plants outdoors. 

This is also when the tomato plants are transplanted one last time. We grow all our beefsteak tomatoes in DIY grow bags but you can of course also plant them directly in the ground.

The “Striped Stuffer” beefsteak tomato is an indeterminate variety and will grow to at least 2 meter / 7 feet tall. 

Beefsteak tomatoes (in May) on one of our Striped Stuffer tomato plants started from seed in February.
Beefsteak tomato plant in May – started from seed in February.

If you use grow bags, containers, or pots you need a minimum soil volume of 20 liters / 5 US gallons / 4.4 Imperial gallons for the indeterminate beefsteak tomato plant to produce well. 

We use DIY medium-sized grow bags (27 liters / 7 US gallons / 6 Imperial gallons) for our indeterminate tomato plants.

Harden you tomato plants

You can start to harden your tomato plants by moving them outdoors for one or two hours per day.

Start slowly and avoid exposing your tomato plants to direct sunlight during the first couple of days. 

Increase the number of hours spent outdoors over the next week to 10 days before you move your plant outdoors permanently.

Caring for your beefsteak tomato plants

Your tomato plants want full sun, plenty of water as well as nutrients and fertilizers throughout the growing season.

Help your tomato plants grow by pinching side shoots as well as providing a proper support structure as the plant grows and develops.

Using liquid fertilizers it is always better to start slow. If unsure, start with half the recommended dosage and then adjust as needed.

Mulching with garden refuse like grass clipping is a great way to add nutrients while helping the soil to retain moisture. 

We do recommend using aged compost or fertilizer for tomatoes for optimal harvest.

To avoid problems with leaf miners, fungus and pests you should water at the base of the plant or use bottom watering. Wet leaves are more likely to attract fungus and mildew.

Also keep plants 50 cm / 20 inches apart to ensure proper air circulation. Plants cramped together are more likely to attract pests, fungus and mildew.

If you spot leaves that are infected with for example leaf miners your first instinct should be to remove and dispose of the leaves. Do not put them on your compost. 

Read Composting tips for beginners for more useful tips and advice on how you too can start a compost at home.

Next, if possible, separate your plant from your other plants and vegetable gardens. This is another advantage of growing plants like tomatoes in grow bags.

If the problem persists, treat the plant with an organic pesticide/insecticide like Neem oil. 

We do not use non-organic pesticides/insecticides why we are unable to recommend any products.
Yellow flowers on a seed started Striped Stuffer beefsteak tomato plant
Nothing says summer like flowering beefsteak tomato plants
Helpful resources:

MDPI

NC State Extension

Meet the author: Mattias is an experienced gardener spending most of his free time on his knees among herbs, plants and garden vegetables. For the past two years he has been sharing gardening projects and how-to tutorials on the NordicLavender website and YouTube channel.