The Definitive Guide to Storing Bulbs: Ensuring Blooms Year After Year

For many gardeners, the vibrant burst of color from spring and summer bulbs is a highlight of the growing season. However, the beauty fades as the season ends, and what’s left are the seemingly unassuming bulbs. The crucial question then arises: how do you store these treasures so they can delight us again next year? Proper bulb storage is the key to success, preventing rot, disease, and desiccation. This comprehensive guide will walk you through every step of the process, ensuring your bulbs are kept safe and sound until planting time.

Understanding Bulb Types and Their Storage Needs

Before diving into the storage process, it’s essential to understand that not all bulbs are created equal. Different types have varying storage requirements. Broadly, we can categorize them as:

• Hardy Bulbs: These bulbs, such as tulips, daffodils, hyacinths, and alliums, are generally cold-hardy and can often remain in the ground over winter in many climates. However, if you live in an area with particularly wet or poorly drained soil, lifting and storing them may be beneficial. They also might need lifting if you want to move them or if their flowering has decreased over time.
• Tender Bulbs: These bulbs, including dahlias, gladioli, cannas, and caladiums, cannot tolerate frost and must be lifted and stored indoors over winter. They are more susceptible to rot and need extra care during the storage process.
• Summer-Blooming Bulbs (sometimes treated as tender): Examples include begonias, lilies (some), and certain varieties of crocosmia. Many of these aren’t technically “true bulbs” but have similar storage needs. Their handling falls between hardy and tender.

Knowing the type of bulbs you have is critical to ensuring their survival over winter. Always check the specific needs of your varieties.

Step-by-Step Guide to Storing Bulbs

Regardless of the type of bulb, the general steps for successful storage are similar, with slight adjustments based on their hardiness. Here’s a detailed breakdown:

1. Knowing When to Lift Your Bulbs

The timing of lifting bulbs is crucial. Lifting too early or too late can negatively impact their ability to store energy and flower the next season. Here’s what to consider:

• Hardy Bulbs: For hardy bulbs you wish to lift, wait until the foliage has completely yellowed or withered and is easily pulled from the ground. This usually happens about 6-8 weeks after the blooming period. The foliage is crucial for photosynthesis, allowing the bulb to store energy for the next year’s growth. If you lift them too early, the bulbs might not be ready to store well.
• Tender Bulbs: Lift tender bulbs after the first light frost has killed the foliage. This usually occurs in late autumn. Wait for a few days after this first frost to allow the bulb to begin its dormancy. Don’t wait too long as extended cold can damage or even rot the bulb.
• Summer-Blooming Bulbs: Lift these before the first frost or when the foliage begins to die back. The same principles apply as with tender bulbs – don’t allow frost to damage the bulbs.

2. The Lifting Process: Careful Extraction

Once the time is right, it’s time to get the bulbs out of the ground. Here’s how to do it:

• Prepare the Area: Gather your tools, including a garden fork or spade, and be ready with a tray or container to hold the lifted bulbs. It’s best to work on a dry day when the soil isn’t soggy.
• Dig Carefully: Using a garden fork or spade, carefully dig around the bulbs, keeping a good distance from their base to avoid damaging them. Gently lift them from the soil, being mindful not to puncture the bulbs. A garden fork is generally preferred over a spade for this process as it causes less damage to the bulbs.
• Clean the Bulbs: Gently remove excess soil from the bulbs using your hands or a soft brush. Avoid washing them unless absolutely necessary, as excess moisture can lead to rot. For really stubborn dirt, using a dry cloth is best or even lightly brushing dry dirt away.
• Inspect for Damage or Disease: As you clean the bulbs, inspect them carefully for signs of rot, disease, or damage. Discard any bulbs that are soft, mushy, or exhibit mold or disease symptoms. Keeping damaged bulbs can spread issues to the healthy ones.

3. The Drying Stage: Curing for Storage

After lifting and cleaning, bulbs need to be cured or dried properly before being stored. This step is critical to prevent rot and fungal diseases. Here’s how to do it:

• Ideal Conditions: Find a dry, well-ventilated area that is out of direct sunlight. A shed, garage, or porch can work well, provided it’s not damp. Ensure the area has some airflow and doesn’t allow condensation to accumulate on the bulbs.
• Layout: Place the bulbs in a single layer on trays, racks, or cardboard boxes lined with newspaper or cardboard. Avoid piling them on top of each other, which can restrict airflow and cause moisture buildup.
• Air Circulation: Ensure there is good air circulation around the bulbs. You can use small trays, or use baskets or perforated containers. Leave ample space between the bulbs to allow air to circulate and prevent moisture from becoming trapped.
• Drying Time: The drying time can vary depending on the type of bulb and the ambient conditions, but usually, a few days to a few weeks is sufficient. Bulbs should be left to dry until the outer layer is dry and papery. Once cured the stems should easily be removed from the bulb.

4. Preparing for Long-Term Storage

Once the bulbs are cured, it’s time to prepare them for long-term storage. Here’s what to do:

• Remove Dried Stems and Foliage: Once cured, gently remove any remaining dry stems or foliage from the bulbs. These are no longer needed and can potentially harbor pests or diseases.
• Label Bulbs: If you have multiple types of bulbs, make sure to label them clearly. Use labels that are weather-resistant and won’t easily fade or rub off. Include the name of the bulb and any other important details, such as color or variety.
• Choose the Right Storage Medium (Optional): Some gardeners prefer to store bulbs in a medium, such as dry peat moss, vermiculite, or wood shavings. This can help regulate humidity and prevent desiccation. If you choose to use a medium, ensure it’s dry and free from any potential contaminants.
• Individual Wraps (Optional) : Bulbs can also be wrapped individually in newspaper or paper bags, this can help control moisture levels and reduce the chance of the spread of any diseases.

5. Proper Storage Conditions: Temperature and Humidity

The storage environment is vital for maintaining the bulbs’ health over the dormant period. Here are some critical factors:

• Temperature: Generally, bulbs prefer a cool, dry, and dark environment. The ideal temperature for most bulbs is around 40-50°F (4-10°C). However, each type may have slight variations in their ideal temperatures. Hardy bulbs usually can handle slightly lower temperatures, while tender bulbs might be more sensitive to frost.
• Humidity: Humidity should be low, around 50-60%. High humidity can lead to rot, while low humidity can cause bulbs to dry out excessively. Good airflow is essential to maintain the appropriate humidity level.
• Avoid Direct Sunlight: Always store bulbs in a dark location to avoid premature sprouting or damage. Even diffused sunlight can raise temperatures and impact bulb health.
• Pest Control: Check stored bulbs regularly for pests or signs of disease. If pests are found, remove them by hand or use a natural pest control method. You can use sticky traps or a natural pest control method if needed, such as diatomaceous earth.

6. Choosing the Right Storage Location

Selecting the right place to store your bulbs is key. Here are some options:

• Basement: A cool, dry basement can be an ideal spot, provided it’s not too humid. Ensure adequate airflow and monitor for pest activity.
• Garage: A garage can also work well if it’s unheated and frost-free. The area should be dry and away from any stored chemicals or other materials that could harm the bulbs.
• Shed: If you have a shed that’s protected from moisture and extreme temperatures, this can also be a suitable storage location.
• Refrigerator (For some varieties): Some bulbs, like tulips, benefit from a period of cold chilling (around 35-40°F) before planting. Storing them in a refrigerator for a couple of months can improve their flowering. However, avoid storing them near fruits, as the ethylene gas can hinder blooming.

7. Monitoring Your Stored Bulbs

Once your bulbs are stored, it’s not a set-it-and-forget-it process. Regular checks are essential:

• Regular Inspections: Check your stored bulbs every few weeks throughout the winter. Look for signs of rot, disease, or pest infestations. Remove any bulbs that appear unhealthy to prevent problems from spreading.
• Adjust as Needed: Depending on the conditions in your storage location, you may need to adjust temperature or humidity. You can increase airflow by adding more ventilation or use a dehumidifier if needed.
• Discard the Unhealthy Bulbs: If any bulb is clearly unhealthy, it is better to discard it to protect other bulbs.

Special Considerations for Specific Bulb Types

While the general storage principles apply to all bulbs, here are some specific considerations for common types:

Dahlias

Dahlia tubers are prone to rot, so ensure they are thoroughly dried before storage. Some people dust them with sulfur powder to prevent fungus before storing them in dry peat moss or vermiculite.

Gladiolus

Gladiolus corms (not true bulbs) should be cleaned and cured well. Store them in a cool, dry place, ideally in paper bags or mesh bags to allow for good airflow. Gladioli are quite susceptible to fungal diseases if not stored properly.

Cannas

Canna rhizomes, like dahlias, are more fleshy and need thorough drying. Some gardeners store them in slightly moist peat moss to prevent them from drying out excessively. Check regularly to ensure they don’t develop rot.

Lilies

Most lilies are hardy but some varieties benefit from digging up and storing in a cool, dry place, such as a paper bag, to prevent fungal rot over winter. Check the particular variety you have as storage needs vary greatly.

Begonias

Tuberous begonias should be treated similarly to dahlias, ensuring they are cured and stored in a dry medium. They benefit from being stored in a dry place and benefit from individual wrapping in newspaper for extra protection.

Caladiums

Caladiums are tropical bulbs that must be stored indoors. Once cured, store them in a dark, cool, dry location, individually wrapped in newspaper. Check often for any signs of softening which means they are rotting and must be disposed of.

When to Replant Your Bulbs

Knowing when to replant your stored bulbs is as crucial as proper storage. Here’s a general guideline:

• Hardy Bulbs: Plant hardy bulbs in the fall, usually in September or October, before the ground freezes.
• Tender Bulbs: Plant tender bulbs in the spring, after the danger of frost has passed and the soil has warmed up.

Troubleshooting Common Storage Issues

Even with the best care, problems can occur. Here are common issues and solutions:

• Rot: If you notice any bulbs rotting, discard them immediately. Make sure your storage area is dry and well-ventilated, and that bulbs are cured properly before storing. Reduce moisture levels and increase airflow.
• Desiccation: Bulbs can shrivel and dry out if stored in a place with very low humidity. Use a storage medium like peat moss or vermiculite to help maintain moisture levels and check them regularly for excessive dryness.
• Pests: If you find pests, remove them by hand or use a natural pest control method. Check bulbs more frequently and make sure they are stored in a pest free location.
• Premature Sprouting: Premature sprouting can occur if the storage location is too warm. Ensure the storage area is cool enough and away from bright light. Lower the temperature, and remove any sprouts to give your bulb the best chance.

Conclusion

Storing bulbs successfully isn’t difficult, but it does require attention to detail and understanding the specific needs of different types of bulbs. By following the steps outlined in this guide, you’ll be well-equipped to preserve your bulb treasures, ensuring they will return to grace your garden with their vibrant blooms season after season. Remember, preparation is key, so start your bulb storage process correctly and your bulbs will reward you with beautiful displays for years to come!