To speed ripening late in the season, remove the growing tip of each main stem about four weeks before the first expected fall frost. Called "topping," this type of pruning causes the plant to stop flowering and setting new fruit, and instead directs all sugars to the remaining fruit.
You want to start pruning tomato plants a when they get to be about 1 -- 2 feet (30-60 cm.) tall. Any smaller than this, and the plant may not recover from the shock of being pruned. By the time your tomato plant gets to be this size, the plant will have branches coming off the main stem.
From a plant disease perspective it's not too advisable to top your tomato plants. pulling off flowers and suckers are more advisable because you are not creating large wounds.
You can keep tomato plants from growing too tall by regularly pruning them, providing support such as stakes or cages, and ensuring they receive adequate sunlight and nutrients to encourage healthy growth without excessive stretching.
To prune during the growing season, simply remove the suckers. Here's how: Look for the tomato "suckers," which are the side shoots that grow in the "V" space between the main stem and the main branches on your plant.
Most grow to three or four feet tall, although some patio varieties top out at 12 inches. Indeterminate tomato plants, which tend to vine, require trellising or cages, continue to grow, and produce fruit until the first frost.
If an established, or larger plant becomes leggy, then they can often be saved by pruning them well and pinching the top off the plant. This encourages the plant to grow bushier and put its energy into something other than growing tall.
However, tomato plants can be a bit finicky when it comes to getting too close to their tomato neighbors, and they like a bit of space between themselves and their fellow garden companions.
Prune off about a third of the leaves (and flowers, if any are present) at the top of the plant, removing the newest, smallest leaves. This will stimulate the plant to branch out lower on the stem, and eventually to produce flowers and fruit throughout its height.
Some gardeners recommend you “pinch off” the flowers on your tomato transplants during their first weeks of growth, claiming that removing early blossoms: Directs more energy into establishing a strong root system. Results in a larger, sturdier, and potentially healthier tomato plant.
You only need to worry about pruning if you're growing a vining type, aka an indeterminate tomato. Bush tomatoes, or determinate tomatoes, are basically self-pruning because they're meant to only grow to a certain size and then stop.
Starting in mid-August, blossoms on large-fruited varieties will not mature and ripen before the end of the season. Remove blossoms and small fruit to encourage ripening of the remaining tomatoes. Reduce or stop watering about mid- to late-August to stress the plant and encourage ripening.
Also the lower leaves tend to get powdery mildew so it is good to remove them to stop disease spreading.
To speed ripening late in the season, remove the growing tip of each main stem about four weeks before the first expected fall frost. Called "topping," this type of pruning causes the plant to stop flowering and setting new fruit, and instead directs all sugars to the remaining fruit.
This means pinching out the growing tips at the top of the plant and stop the plant growing up any further. Stop off at the top of the plant when there are 3-4 (outside grown) and 4-5 (greenhouse grown) trusses, which are layers of flowers.
Remove "suckers" (small shoots growing in the leaf axils between the main stem and branches). Trim off lower leaves that touch the ground to prevent soil-borne diseases.
Give them consistent watering (deep and infrequent trumps a daily sprinkle), well-draining soil (incorporate generous helpings of compost into beds or containers at planting time), plenty of heat and light (direct, unobstructed sunshine for a minimum of 6 hours daily is best) and a slow-release, balanced fertilizer ...
It is ideal to clip within a few inches of every fruit cluster. If this puts your clips close together it is alright, more is better in this situation. As long as you keep your leader vine well supported and ensure the plant has enough leaves up top to provide canopy, your vines will continue to produce fruit.
Tomatoes love the sunshine. A position in full sun (that means an average of at least eight hours a day) gives the best results in most areas, though if you're in a hot climate you can get away with dappled shade.
Do all tomatoes have to be pinched out? The simple answer is no. With large-fruited tomato varieties such as ox-heart and beef tomatoes, however, the side shoots should be removed. Even with medium-sized indeterminate tomatoes, we recommend only leaving a maximum of two to three shoots, including the main shoot.
ALWAYS prune back to or just above a growing point (branch or bud) or to the soil line. NEVER leave a stem or branch stub. NEVER top a tree to “rejuvenate” growth. Â This ruins the plant's natural shape and greatly increases its susceptibility to diseases, insect pests, and storm damage.