How to Grow Tomatoes from Seeds

Purchase seeds or use seeds from a tomato. You can buy seeds online from seed exchange sites, at nurseries, or from gardeners. You can also find seeds in the gardening section of supermarkets. If you want to extract seeds from a plant, you'll need at least one tomato from that plant. Ensure the tomato comes from a plant grown from heirloom or open-pollinated seeds. If you choose tomatoes from hybrid plants or chemically treated seeds, the results may not meet your expectations. Tomatoes can be categorized as:

• Heirloom or hybrid tomatoes: Heirloom tomatoes have genetic traits passed down through generations without cross-pollination. Essentially, they are purebred. Hybrid tomatoes are a cross between two varieties.
• Determinate or indeterminate growth: This classification is based on the fruiting period. Determinate plants produce fruit for a few weeks, while indeterminate plants bear fruit throughout the season until the climate becomes too cold. Indeterminate plants also grow larger and require more care, such as pruning and staking.
• Shape: Tomatoes are also divided into four types based on shape: globe, beefsteak, paste, and cherry. Globe tomatoes are the most common, beefsteak tomatoes are the largest, paste tomatoes are often used for sauces, and cherry tomatoes are small, bite-sized, and commonly used in salads.

Cut the tomato in half and scoop the pulp into a plastic container. Use a container with a loosely fitted lid to store the pulp and seeds for a few days. A layer of mold will develop on the seeds, which helps eliminate diseases that could affect future tomato plants.

Label the container. If fermenting multiple tomato varieties, label each container with the tomato type to avoid mixing. Loosely cover the container to allow oxygen inside.

Place the container in a warm area away from direct sunlight. The fermentation process can look unappealing and produce a strong odor, so store it in discreet locations like under the sink or in the garage (as long as it’s warm).

Stir the seeds daily until a white mold forms on the surface. This usually takes 2-3 days. Harvest the seeds immediately after mold forms to prevent them from sprouting in the container.

Harvest the seeds. Wear gloves, skim off the mold, and collect the seeds that have settled at the bottom of the container.

Add water to the container to dilute the mixture. Allow the seeds to settle at the bottom, then strain the liquid through a sieve. Be careful not to lose the seeds. Rinse the tomato seeds thoroughly after collecting them in the sieve.

Spread the tomato seeds on a non-stick surface and let them dry for a few days. Ceramic or glass plates, baking parchment, plywood, or window screens work well. Avoid using paper or fabric, as dried seeds can be difficult to remove. Once dry, store the seeds in sealed plastic bags until ready for planting. Remember to label each seed type.

Store the seeds in a cool, dark place. You can also keep them in an airtight container in the refrigerator to simulate winter conditions, but avoid freezing to prevent seed damage.

Sow the seeds and keep the seedlings indoors for about 6-8 weeks before the last frost. To prepare tomato plants for outdoor conditions, start growing seedlings indoors while it’s still cold outside. Early spring frosts can stunt or kill young plants. Starting indoors increases the chances of success.

Purchase peat pots or similar small containers for seedlings. These can be found at nurseries or gardening supply stores.

Fill the pots with a moist soil mixture. The mixture can consist of 1/3 peat moss, 1/3 coarse vermiculite, and 1/3 compost. Ensure the soil is damp before sowing the seeds.

Plant 2-3 seeds in each pot, about 0.5 cm deep. Cover with soil and gently pat down.

Place the pots in a room with a temperature of 21 to 27 degrees Celsius until the seeds germinate. Move the pots to a sunny location or use grow lights once the seeds have sprouted.

Mist the seeds daily for the first 7-10 days. Once sprouts appear, reduce watering frequency. Seedlings are more likely to die from overwatering (causing root rot) than underwatering, so water moderately after germination.

• You can also soak the seed pots in water to allow roots to absorb moisture from below. Misting alone may not provide enough water for the roots.

Check the pots daily. Once the seedlings emerge from the soil, they will grow quite rapidly.

Monitor the plants until they reach at least 15 cm in height. When the risk of frost has passed and the plants have reached the required height, they are ready to be transplanted outdoors.

Harden off the seedlings. About a week before transplanting, gradually acclimate the plants to outdoor conditions. Start by placing them in partial shade and slowly increase their exposure to sunlight each day. Begin with an hour or less and gradually extend the time.

Prepare the garden space. Ensure the soil is well-draining and rich in organic matter.

• Consider adding peat moss to improve drainage. You can also mix in compost.
• To use peat moss, remove about half the soil and mix it with an equal amount of peat moss. Return the mixture to the planting area.

Test the soil's pH level. Tomatoes thrive best in soil with a pH ranging from 6 to 7.

• Local agricultural extension offices can provide soil testing kits along with instructions. After adjusting the pH, you need to test it again.
• If the pH is below 6, you should add dolomite lime to the soil to raise the pH.
• If the pH is above 7, you can lower it by mixing granular sulfur into the soil.

Dig a hole about 60 cm deep. The hole should be deep enough so that when you plant the tomato seedling, only a quarter of the plant remains above the ground. Add a handful of organic matter like compost to the bottom of the hole. This will help the plant grow and prevent transplant shock.

Carefully remove the plant from its pot and place it in the hole. Try not to damage the roots during the process. Position the plant so that when you fill the hole, the first set of leaves touches the soil surface. Gently pat the soil after planting.

• Remember to trim any leaves at or below the soil level. Tomatoes can develop diseases if leaves come into contact with the soil.

Fertilize the plant. You can use fish meal, chicken manure, or pre-mixed organic fertilizer with low nitrogen or high phosphorus content. Water the plant carefully afterward. Fertilize once a month.

Place a stake or trellis next to the tomato plant. This will provide support as the plant grows and make it easier to harvest the fruit. Be careful not to damage the roots.

Water and fertilize the plant regularly. Water the base of the plant to prevent mold from developing on the leaves. Use liquid seaweed fertilizer for watering and spread a layer of compost directly onto the soil around the plant. Repeat this weekly to boost fruit production.

Prune the suckers. To encourage healthier growth and higher fruit yield, pinch off the suckers by hand as they appear. Suckers grow in the junctions between branches and the main stem. Leave a few suckers near the top to prevent sunscald.

Harvest the fruit at its peak. About 60 days after planting, tomatoes start bearing fruit. Check the fruit daily as they begin to ripen to ensure the best flavor. Gently twist the stem to pick the fruit, avoiding any damage to the branches.