Tomato Suckers: What They Are and How to Manage Them

Tomato suckers are the small shoots that grow in the V-shaped crotch between the main stem and branches of tomato plants. Removing them properly directs the plant's energy toward fruit production rather than excessive foliage, resulting in larger, earlier-ripening tomatoes and improved air circulation to prevent disease.

What Exactly Are Tomato Suckers and Why Do They Matter?

Tomato suckers (also called side shoots) emerge from the axil where leaf stems meet the main plant stem. These fast-growing shoots would naturally develop into full secondary stems with their own branches and fruit clusters if left unchecked. While they might seem harmless, unmanaged suckers create dense foliage that:

• Diverts energy from fruit development to leaf production
• Creates humid microclimates that promote fungal diseases
• Makes harvesting difficult due to tangled growth
• Delays ripening by spreading the plant's resources too thin

Proper sucker management is one of the most impactful techniques for home tomato growers to maximize both yield quality and quantity. The University of California Agriculture and Natural Resources confirms that strategic pruning can increase fruit size by 20-30% compared to unpruned plants.

How to Identify Suckers: The Visual Guide

Suckers appear as small shoots growing from the axillary bud - the point where a leaf stem connects to the main plant stem. They typically emerge when plants reach 12-18 inches tall. Early identification is crucial because:

• Young suckers (2-4 inches long) snap off easily with minimal damage
• Mature suckers require cutting and create larger wounds vulnerable to disease
• Missed suckers quickly become major stems that compete with the main plant

When Timing Makes All the Difference

The optimal time for sucker removal depends on both plant development stage and environmental conditions:

Plant Stage	Recommended Action	Frequency
Early growth (12-18" tall)	Remove all suckers below first flower cluster	Every 3-4 days
Flowering stage	Maintain 1-2 main stems; remove excess suckers	Twice weekly
Late season (30+ days before frost)	"Top" plants by removing growing tips	Once

According to Cornell University's College of Agriculture and Life Sciences, the morning is the ideal time for pruning when plants are turgid (full of moisture), making clean breaks easier and reducing stress. Avoid pruning during wet conditions which increases disease transmission risk.

The Step-by-Step Sucker Removal Process

Follow this professional technique for clean, effective sucker management:

1. Identify the sucker growing from the leaf axil
2. Position your thumb on the base of the sucker
3. Apply gentle downward pressure with your thumb while supporting the main stem
4. Break the sucker cleanly with a quick flicking motion (no tools needed for suckers under 4")
5. Inspect for complete removal - no stub should remain
6. Sanitize hands or tools between plants when dealing with diseased specimens

For larger suckers (over 4 inches), use sterilized pruning shears to make a clean cut close to the main stem without damaging the bark. The American Horticultural Society recommends dipping tools in a 10% bleach solution between plants when disease is present.

Context Boundaries: When NOT to Remove Suckers

While sucker removal generally benefits indeterminate tomato varieties, there are important exceptions where minimal pruning is preferable:

• Determinate varieties (bush tomatoes) naturally stop growing at a certain height and require little to no pruning
• Extreme heat conditions (above 90°F/32°C) where foliage provides necessary fruit shade
• Container gardening with limited root space where some foliage helps maintain moisture balance
• Late-season plants where new growth won't have time to produce mature fruit

The USDA Agricultural Research Service notes that in regions with intense sunlight, maintaining some foliage can prevent sunscald on ripening fruit - a trade-off between maximum yield and fruit quality.

Avoiding Common Sucker Management Mistakes

Even experienced gardeners make these critical errors that can damage plants:

• Over-pruning - Removing too many leaves reduces photosynthesis capacity
• Leaving stubs - Incomplete removal invites disease and regrowth
• Pruning during wet weather - Spreads fungal and bacterial diseases
• Using dirty tools - Transfers pathogens between plants
• Removing all suckers on indeterminates - Creates single-stem plants vulnerable to breakage

Research from the University of Florida's Institute of Food and Agricultural Sciences shows that plants with 2-3 main stems typically produce the highest quality yield, balancing fruit production with plant stability.

Tailoring Your Approach to Tomato Varieties

Different tomato types require distinct sucker management strategies:

• Indeterminate varieties (most heirlooms and vining types): Require regular sucker removal to maintain 1-3 main stems
• Determinate varieties (Roma, Celebrity): Naturally bushy; remove only diseased or damaged growth
• Cherry tomatoes: Can handle more suckers but benefit from selective pruning for better air circulation

For container gardeners, the Ohio State University Extension recommends allowing one additional sucker to develop on indeterminate varieties to compensate for restricted root growth.

Frequently Asked Questions

Can I root tomato suckers to grow new plants?

Yes, healthy suckers 4-6 inches long can be rooted in water or potting mix. Remove lower leaves, place in moist medium, and keep in indirect light. Most will develop roots within 7-10 days, creating genetically identical plants to the parent.

How many main stems should I maintain on indeterminate tomatoes?

Most gardeners maintain 1-3 main stems depending on support system and space. Single-stem plants produce earliest but smallest yields. Two-stem systems offer the best balance of yield and manageability for most home gardens. Three stems maximize production but require substantial support.

Will removing suckers prevent all tomato diseases?

While sucker removal improves air circulation and reduces humidity around fruit (helping prevent fungal diseases like early blight), it won't prevent all diseases. Combine pruning with crop rotation, proper spacing, and resistant varieties for comprehensive disease management.

What should I do with removed suckers?

Healthy suckers can be composted if disease-free. Diseased material should be bagged and discarded. As mentioned previously, suitable suckers can also be rooted to create new plants. Avoid leaving prunings on the ground near plants as they may harbor disease spores.