By Peter Sandercock
You can almost taste sunlight when you bite into a fresh, perfectly-ripe tomato. Capturing this flavour inspires many people to grow their own. Besides, who doesn’t enjoy nibbling on cherry tomatoes from a pot on their deck?
It can be overwhelming to choose which varieties to try. Start by thinking about why you are growing them. Maybe you are interested in growing heirloom varieties or the perfect beefsteak tomato for your hamburger. Cherry tomatoes are great for snacking and adding to salads while bush tomatoes give fruit all at one time so are ideal if you are interested in canning them or making a large batch of salsa. Also, consider when you want to start eating them. Check out the days to maturation as a guide to which varieties ripen early. There are long keeper varieties that will stay fresh for several months. Be adventurous! There are many heirloom varieties and always new varieties coming out.
Once you have made your choice, set up a place to start your seedlings. Tomatoes love heat–especially consistent heat–so choose a warm location or use a germination mat. A sunny window is great, but you can also use grow lights. Seed your tomatoes in mid-March to early April so they are large enough to go outdoors in June.
For best results, use a seed starting soil mix to grow your tomatoes. Dampen the soil mix and plant two or three seeds together less than ½ inch (1 cm) deep. They should sprout in one or two weeks. As mentioned, place them in a warm, sunny location or near a grow light so that they don’t have to reach for the light. If they start to stretch then they need more light: either strong, direct sunlight or 14 -18 hours under grow lights.
To grow strong stems, tomatoes need to ‘sway in the breeze’. Use a fan to create a light breeze (not a wind storm) a few times throughout the day. Don’t leave the fan on all the time as it may dry out your seedlings. Transplant them into larger pots as soon as the first real leaves appear and then again about two weeks later.
You can skip this step and buy tomatoes that are already started from your local greenhouse. This way you can ask the greenhouse staff what the popular varieties are. Look for plants that have not stretched and have active white roots. If the weather is not warm enough to plant outside, then treat them as mentioned above until it is time to plant.
Before planting in the garden, prepare the area by covering the soil with black plastic for a few weeks. This will warm the soil and translate into happier tomato plants and an earlier harvest. Tomatoes love heat. Many people use plastic tomato covers that can be filled with water to add heat units and protect the tomatoes from the elements. The covers allow you to plant earlier and you can leave them on until the weather warms up.
Plant tomatoes deep. In fact, you can plant them all the way up to the top few leaves. Tomatoes can develop roots along their stems. The bumps along the stem are actually dormant roots and therefore transplanting deeper provides more roots and stronger plants. You can either dig a deeper hole or simply dig a shallow trench and lay the plant sideways. It will straighten up and grow toward the sun. If you are staking the plant, be careful not to pierce the stem or roots with the cage. Plant in a sunny location as tomatoes need at least 5 hours of direct sunlight to thrive and develop a sweet flavour.
After planting, it is a good idea to mulch. Mulching conserves water and prevents soil-borne diseases from affecting the plants. Consider red plastic ground covers as mulch. It sounds like an old wives’ tale, but studies confirm that the color red makes tomatoes grow more quickly and stockier. Why? The color red makes the tomato believe that they are overcrowded and encourages the plants to battle for dominance resulting in more tomatoes on healthier, bushier plants!
How, when and where should I prune my tomato plants? This requires finding out whether you have a determinate (usually bush style tomatoes) or indeterminate tomato plant.
Determinate type tomatoes tend to set and ripen their fruit all at one time and usually do not require too much pruning.
Indeterminate type tomatoes (staking tomatoes) grow very tall and require pruning. These tomatoes will set fruit earlier if you pinch off the tips of the main stems in early summer. You can further prune the plants by removing the leaves from the bottom 1 inch (2.5 cm) of stem. These are usually the first leaves to develop fungus problems as they get the least amount of sun and are closest to the soil. You can also remove leaves that sprout in the crotch joint of two branches. This growth will not produce tomatoes and the energy to grow these branches takes away from producing fruit. Don’t over prune.
The tomato needs leaves for photosynthesizing and creating the sugars that flavour your tomatoes. Towards the end of the season, prune off smaller fruit and flower buds so the tomato will concentrate on growing the larger fruit before the frost.
One of the most important tasks in growing successful tomatoes is water management. Water deeply and consistently. Uneven or erratic watering leads to blossom end rot (calcium deficiency) and cracking. You can reduce the water during the ripening stage to encourage the development of sugars for sweeter tomatoes.
Finally, fertilizer will improve your yields. Stronger plants also mean less disease. Begin fertilizing right after transplanting with a high phosphorous mix such as 10–52–10 for 3 to 4 weeks. After that a balanced mix such as 20-20-20 once a week is recommended.
Good to Know: The three numbers on the fertilizer bag indicate the ratio of three key nutrients included in all fertilizers: nitrogen, phosphorus and potassium, listed in this order. Meaning if a bag reads 21-4-3, it contains 21 per cent nitrogen, 4 per cent phosphorus and three per cent potassium. Nitrogen boosts growth making plants a nice healthy green colour. Phosphorus feeds seedlings and stimulates new root growth. Potassium helps with all around vigour and plant health and strengthens resistance to disease and stress.
As with all gardening, the joy is in the doing and seeing what you can grow. Good luck with your tomato crop!
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