Tomatoes are grown in nutrient rich loam or sandy loam soils under warm weather. However, other soil types will support moderate growth of tomatoes. Grown from seed or through asexual propagation, tomatoes are ready for harvest in 80 days or 8 to 9 weeks. Tomato plants require even watering and at least 6 hours of full sun daily to do well.
The scientific name of tomatoes is Lycopersicon esculentum. Lycopersicon means “wolf peach”. This name is said to have been derived from German werewolf myths. The backstory is that the tomato belongs to the nightshade family. In this family are eggplants, peppers and potatoes as some of the family members. In mythology, the deadly nightshade family was used to summon wolves. This is where the tomato derived its “wolf peach” name because of its size resembling a peach.
Table of Contents
Types of Tomatoes to Grow
Before growing tomatoes, consideration is given to the type of tomato to grow. The two main tomato classes are determinant and indeterminate tomatoes. The fundamental difference between the two is life span and fruit production.
The determinant tomato typically fruits for a short period lasting some 2 weeks. Once the fruiting, which happens all at once, is completed, the plant begins to diminish in energy and dies. Furthermore, the determinant tomato has a fixed mature size of about 1.5m or 5 feet in height. It is shorter in height, compact and bushy compared to the indeterminate tomato.
On the other hand, the indeterminate tomato offers continuous fruit production throughout the season. It is also known as the vining tomato. The tomato plant typically grows in length to as much as 2 meters or 6.5 feet. Unlike the determinant tomato, the indeterminate tomato requires pruning for quality and maximum fruit production. See caring for tomato plants below.
Nevertheless, most tomato varieties grown today are indeterminate tomato varieties. They are grown in home gardens as well as at commercial scale on farms.
Jump to our in depth feature on Indeterminate Tomatoes.
Which tomato variety to grow
There are thousands of tomato varieties available to grow today. This big number has come about through mutation and breeding over time. There are many hybrid tomato seeds available for purchase. Each of these tomato varieties were developed to take care of specific issues.
Some hybrid tomatoes were developed to be resistant to certain common tomato diseases and pests. Some were designed to thrive in lower temperatures than normal while others can fruit in drier conditions. There are many different characteristics associated with each of this wide range of tomato variates.
Which tomato to grow is determined by what each variety brings to the table. Most commercially available tomato seed varieties provide full information on the packaging to assist growers in making informed decisions. It is thus recommended to take time to read packaging information.
Practical Steps to Growing Tomatoes
Some of the practical considerations when growing tomatoes include growing method, soil type to use, planting methods, watering approach and best fertiliser to use among other considerations.
Growing tomatoes from seed
When growing tomatoes from seed, seed is planted indoors several weeks before the end of winter. By the last day of frost, the seedlings are ready for transplanting outdoors in warmer weather.
Most growers who start tomatoes indoors practice hardening. This means 2 to 4 weeks before the last day of frost, the seedlings are taken outside for some 1 to 2 hours. The number of hours per day outside is increased steadily until frost has ended. The seedlings are then planted in the ground.
Hardening is done to acclimatize the tomato plants to the outside elements namely temperatures, direct sun light and wind.
Propagating tomatoes from seed is the most common way of growing tomatoes. In agricultural science, this is known as sexual propagation.
Nevertheless, there are numerous tomato varieties to grow. Some of the most popular ones include sungold, early girl and yellow tomatoes. Tomato seed is available online or in gardening stores.
Growing tomatoes through vegetative propagation
When growing tomatoes through vegetative propagation, a tomato plant sucker is removed from the parent plant. It is placed in a jar with water. Suckers or side shoots of between 10 and 20 cm long are used for this purpose. After several days, the sucker grows some clearly visible roots.
Once the roots appear the propagated sucker is transplanted into the ground or container. The tomato plant will grow into a mature plant like any other tomato plant with fruit identical to its parent.
This alternative method of planting tomatoes is also known as asexual propagation. Asexual propagation is mostly used in cases where original seeds are unavailable. This is common with some rare heirloom tomato varieties.
Soil for growing tomatoes
Tomatoes are best grown in fertile, well-drained, loam or sandy loam soils. The soil must be slightly acidic with a pH level not exceeding 7.5. If the soil is too acidic, agricultural limestone is used to neutralize the pH to an ideal level.
For flavorful tomatoes, a good balance of nutrients must be attained. Phosphorus and potassium play an important role in the final taste of the tomato fruit. Some growers add Epsom salt to tomato plants for this reason. However, Epsom salt is recommended where the soil is deficient in magnesium and/or sulfur.
Overall, tomatoes tend not to be too fussy about growing medium used. If the soil is clay, for example, this can be amended by adding some sand to it. Tomatoes will do moderately well in a wide range of soil types including native garden soil. However, for serious commercial growing of tomatoes, it may be necessary to have a soil test done first.
As an easy way to get started, commercially available ready-to-grow potting mixes such as these ones help jump start beginner tomato growers.
Planting tomatoes
When planting tomatoes, planting holes are first created in the ground. Each planting hole takes a single seedling. An ideal planting hole has a diameter of 10cm (or 4 inches) and a depth of 10cm (or 4 inches) as shown in the diagram.
The seedlings are planted 30cm or 12 inches apart. If rows are utilized, these are 60 to 90cm apart or 2 to 3 feet apart.
Some growers mix in other crops with tomatoes as a way of controlling pests.
Tomato companion plants include garlic, chives or asparagus among others. These companion plants can be interplanted in-between the tomato plants. Adding companion plants to the tomato garden is mostly done by home gardeners and is little practised at scale.
Watering tomatoes
Tomatoes grown in the ground typically require between 1.5cm to 5cm (1 to 2 inches) of water per week. A mature tomato plant requires 2 to 3 liters of water daily.
Local climatic conditions will also determine how much additional watering will be required.
Tomatoes must be watered evenly avoiding periods of dryness. Dryness causes the fruit to crack or split open. Mulch is utilized around the tomato plant base to reduce rapid loss of moisture from the soil.
Furthermore, poor watering results in flowers dropping and the tomatoes suffering from the dreaded blossom end rot as pictured.
Recommended watering times for tomatoes are early morning and early afternoon. Early morning and/or early afternoon watering affords enough time for the water which may have settled on the leaves while watering to evaporate.
Watering the leaves directly is deliberately avoided. This is important in reducing the risk of fungal problems.
Fertilizing tomato plants
Tomatoes are heavy feeders and will require fertilizer in most cases. A generous amount of well-rotted manure is added to the planting hole at planting time at 20 to 30cm deep (8 to 12 inches).
While this is the simplest and quickest way to fertilize tomato plants, manure tends to be low in phosphorus. In response, tomato growers use bone meal in small quantities to amend this shortcoming. Bone meal is made from ground up animal bones, usually beef bones.
Commercially available fertilizer is also used on tomatoes. This is usually referred to as NPK. NPK stands for nitrogen (N), phosphorus (P), and potassium (K).
The catch in fertilizing tomatoes is to avoid overdoing it. A simple NPK ratio for tomatoes is 3-4-6 or 4-7-10. Excessive nitrogen produces a lush foliage devoid of fruit. To avoid this misfortune, unless prescribed, the nitrogen number should not be bigger than the rest of the numbers in the configuration.
Once the initial planting fertilizer is applied, be it manure or commercial NPK, more fertilizer is added to the plant every 3 to 4 weeks until the season is over.
Tomato fertilizer can be granular or foliar fertilizer. Manure and NPK are examples of granular fertilizers. Foliar fertilizer is dissolved in water and applied to the leaves of the tomato plant. An example of this type of fertilizer would be Epsom Salt also known as Magnesium Sulfate – MgSO4.
The following table can be used as a guide when fertilizing tomatoes using NPK.
| Timing after Transplanting | NPK Ratio | Comment |
|---|---|---|
| 1 week | 10-40-10 | High in phosphorus |
| 2-3 weeks | 20-10-10 | New leaves appear, high in nitrogen |
| 4-6 weeks | 12-12-17 | When flowers form & fruit develop, high in potassium |
Caring for the Tomatoes
Growing good quality tomatoes involves caring for the tomatoes. Indeterminate or vining tomatoes require special care in order to produce best yield and best fruit quality.
Indeterminate tomato varieties are staked, caged or trellised in order to grow upright. This support is easier implemented at the planting stage than at a later stage.
Vining tomatoes are pruned as part of plant care to encourage better fruit production. Pruning is done by removing shoots or suckers growing sideways on the main stem (as shown by yellow arrow). Pruning is done throughout the season.
Depending on tomato variety, suckers may return to the same spot after pruning. This is common with some cherry tomatoes. Another round of pruning will thus be required.
Regular even watering of the tomato plant is important to avoid the fruits splitting open. Soil around tomato plants should not be allowed to dry. Splitting and other problems become inevitable when the plants are eventually watered. Over watering the plant is also another cause of tomato splitting. It also results in leaching which leads to deficiencies due to loss of important nutrients.
Finally, tomatoes are sun loving plants. They should receive at least 6 hours of direct sunlight per day for optimal performance.
Known Tomato Pests and Diseases
Tomatoes are prone to attack by a variety of pests and diseases. Tomato pests and diseases are minimised by better care of the tomatoes.
Tomato varieties chosen for planting also play an important role in controlling and reducing the risk of disease. Furthermore, plant rotation is an effective way of controlling tomato pests and diseases.
Certain pungent plants such as marigold, onions, peppers and basil are useful tomato companion plants. These plants discourage the invasion of certain pests.
Tomato growers do well to be familiar with tomato diseases. The following table shows the most common tomato diseases.
| Disease Name | Information |
|---|---|
| Early Blight | A fungus that lives in the soil. Causes plant leaves to turn yellow and die. Mulching helps prevent the fungus from climbing up the plant. |
| Fusarium Wilt | Lives in the soil. Causes tomato leaf stems to drop and branches to wilt. Eventually kills the whole plant. It is controlled by disinfecting tools and growing resistant tomato varieties. |
| Septoria Leaf Spot | Infected leaves turn yellow & brown and then die. Remove infected leaves. Use copper based fungicides. |
| Verticillium Wilt | Lives in the soil. Causes tomato plant leaves and stem to dry. Attacks stem tissue. Plant resistant tomato varieties e.g Better Boy, Wonder Boy |
| Late Blight | Fungus that lives in the soil. Attacks stems and leaves causing them to rot. Pathogen is also carried by potatoes. Immediate removal of infected plants helps halt spread to healthy plants. |
| Southern Bacterial Wilt | Soil borne tomato disease. Attacks leaves turning them yellow. No cure. Immediate removal of infected plants helps halt spread to healthy plants. |
See our feature on Causes of Black Spots on Tomatoes
Tomato diseases and pests (Video)
In this video, various tomato diseases are covered. They are identified and methods of controlling them discussed.
Growing Tomatoes in Containers
Growing tomatoes in containers is a viable alternative to putting them in the ground. Growing potatoes in containers saves space. Furthermore, this makes it easier to manage the plant itself, diseases and pests.
Containers for growing tomatoes can be 30cm (12 inches) in diameter and 45cm (18 inches) deep. The container should have drainage holes beneath. The easiest tomato growing medium to use with containers is commercially available potting mix such as this one.
Native garden soil can also be used to grow tomatoes in pots. To eliminate soil borne diseases, pests and weeds, some sources recommend heating the soil in an oven for 1 hour at 210 degrees or 98 degrees Celsius.
Soil in containers tends to quickly loose its nutrients due to the constant draining of the pot through watering. Regular soil fertilization is therefore required. Any yellowing of leaves may be a sign of magnesium deficiency. This can easily be remedied by applying Epsom Salt as explained in this article.
Although indeterminate tomato varieties can be grown in containers, determinate varieties tend to be easier to manage. Indeterminate tomato varieties grown in containers will require the same level and type of care as earlier explained.
Harvesting Tomatoes
Most tomato varieties are harvested within 80 days of planting. The tomato fruit is ready to harvest when it changes color from green to streaks of red. In such cases it finishes ripening in storage.
However, many home tomato growers prefer to let the fruit finish ripening on the plant. This produces fresh tomatoes full of flavor.
In addition, to minimise the risk of the harvested tomatoes rotting, the tomatoes should be dry when harvested. Equally, harvesting should take place in dry weather and not when it is raining.
Furthermore, the stem should remain attached to the tomato to encourage ongoing flowering. Cherry tomatoes are normally harvested in clusters.
How to store harvested tomatoes
Once harvested, fresh whole tomatoes are stored at 60 degrees (or 15 degrees Celsius). Culinary experts recommend storing ripe tomatoes with stem-side down. They are placed in paper towels and into a container.
Freshly harvested tomatoes are not stored in the refrigerator. The refrigerator affects the flesh of the tomato causing it to become mashy.
However, once the tomatoes have been cut they can be stored in the refrigerator. They should, however, be used as soon as possible whilst they are still flavorful.
Conclusion
Growing tomatoes is fairly an easy and straightforward process. It begins with choosing the correct variety to grow followed by making the right soil preparations. Once the tomato plant is transplanted into the ground, great care is required to reduce risk of disease and pests as well as to increase yield. The best tomatoes in flavor are those harvested fully ripened. They are then stored whole outside the refrigerator at an appropriate outside temperature.
Jump to our in depth feature on Indeterminate Tomatoes.
