Preserving gladioli corms until spring planting is a task that requires strict adherence to temperature and humidity modes, especially if you plan to use a household refrigerator. The main problem is not so much the cold as the ability of the planting material to “breathe” and the risk of drying out or, conversely, rotting in a confined space.
The refrigerator compartment is an ideal place for overwintering the bulbs, since it maintains a stable temperature necessary for the plant to rest. However, simply putting the tubers on the shelf is not enough, because they need a special environment that will prevent moisture loss and protect against mold.
In this article we will analyze in detail all the suitable materials for packaging, discuss the nuances of preparing the bulbs and answer the question of what exactly is the best way to store gladioli in the refrigerator in order to get healthy planting material in the spring.
Preparing corms for winter storage
Before deciding which container to place the bulbs in, it is necessary to thoroughly prepare the planting material, since 90% of wintering success depends on this. The corms dug up after the first frost must be cleaned from the ground, the baby separated and dried at a temperature of about 25-30 degrees for a month.
Critical The stage is to remove the old bottom part and remnants of scales, since it is under them that fungal spores and thrips most often hide. If you do not remove old scales, the risk of rot developing in a refrigerator where ventilation is limited increases many times over.
⚠️ Attention: Do not store bulbs with visible signs of rot, mechanical damage or stains. One diseased bulb can infect the entire planting material in the refrigerator in a few weeks.
After cleaning and drying, it is recommended to treat the corms with a solution of a fungicide or insecticide. You can use Fundazol or Maxim to protect against fungi, as well as drugs against thrips, which are especially active in warm conditions, but go into suspended animation in the cold.
Complete dried planting material is ready for packaging. It is important that the surface of the bulb is dry to the touch, otherwise moisture will be preserved inside the package and cause mold.
Requirements for temperature and humidity in the refrigerator
For successful storage of gladioli, it is necessary to create conditions as close as possible to natural ones, but with a controlled climate. The optimal temperature for most varieties is considered to be from +3 to +5 degrees Celsius, which corresponds to the standard temperature on the bottom shelf of the refrigerator or in the vegetable compartment.
Air humidity should be maintained at 60-70%. If the humidity is too low, the corms will begin to shrink and lose turgor, which will lead to depletion of nutrients. If the humidity is too high (>80%), there is a high risk of bud awakening and premature root growth.
You should not place the bulbs next to fruits, especially apples and pears, as they emit ethylene. This gas accelerates ripening, but is harmful for gladioli bulbs, as it can stimulate premature germination or, conversely, inhibit development.
Use a thermometer-hygrometer to monitor conditions in the storage area, especially in the first weeks. This will help you notice deviations in time and correct the position of the container.
Paper packaging: a classic and reliable method
Paper remains one of the most popular storage materials, as it has excellent hygroscopicity and allows the bulbs to breathe. Regular office paper, newspapers (with caution due to printing ink) or special craft bags are great for wrapping each bulb individually.
The paper-wrapped corms are placed in a cardboard box or plastic container with holes. The paper absorbs excess moisture if it suddenly appears, and gradually releases it back if the air becomes too dry, creating a stable microclimate.
Is it possible to use colored magazines?
It is not recommended to use pages of colored glossy magazines, since the chemical components of the paint can negatively affect the skin of the onion with prolonged contact in a confined space. It is better to use clean white paper or craft paper.
If you use newspapers, make sure that the text is not imprinted on the wet areas of the bulb. It is best to wrap each corm in 2-3 layers of paper, creating a kind of “cocoon.”
The cardboard boxes in which you put the bundles should also be dry and clean. You can place additional sheets of paper or napkins between the rows of bulbs for better ventilation.
Using peat, sawdust and wood shavings
Natural bulk materials such as dry peat, hardwood sawdust or wood shavings create an excellent environment for corms. They not only protect against mechanical damage, but also regulate humidity, preventing drying out.
A layer of filler is poured into a container or tight bag, then the bulbs are laid, which are again sprinkled with filler. It is important that sawdust or peat are completely dry, otherwise they will become a source of infection.
☑️ Preparing bulk filler
It is not recommended to use pine sawdust due to the content of resins, which can be aggressive to plants. Sawdust from birch, aspen or oak is best suited, which can be pre-calcined for disinfection.
This method is good because the bulbs are in the dark and isolated from each other, which prevents the spread of diseases if one of them begins to deteriorate.
Plastic containers and bags with perforations
Plastic containers are convenient due to their compactness and transparency, which allows you to visually monitor the condition of the planting material. However, plastic does not breathe, so the use of solid sealed containers without ventilation is unacceptable.
It is necessary to make holes in the lid and walls of the container with a diameter of 5-10 mm for air circulation. The distance between the holes should be about 5-7 cm to ensure uniform gas exchange throughout the entire volume.
Several layers of paper towels or napkins can be placed at the bottom of the container to act as an adsorbent. They will need to be checked periodically and replaced if they become damp.
Do not fill the container to the brim, leave about 20% free space for free air circulation around each bulb.
Comparison of materials: characteristics table
To make it easier for you to choose what to store gladioli in refrigerator, we have prepared a comparison table of basic materials. It will help you weigh all the pros and cons of each packaging method.
| Material | Ventilation | Moisture exchange | Risk of rot | Convenience |
|---|---|---|---|---|
| Paper | High | Good | Low | High |
| Peat/Sawdust | Average | Excellent | Average | Average |
| Plastic (with holes) | Low/Average | Weak | Average | High |
| Stocking (nylon) | Maximum | Absent | High (drying out) | Low |
As can be seen from the table, paper and natural fillers provide the best balance between ventilation and moisture retention. Plastic requires more careful monitoring, and nylon stockings, popular in the past, are considered less reliable today due to the risk of drying out in refrigerator operating conditions.
Frequent problems when storing in the refrigerator
Even with proper packaging, problems may arise that you need to know about in advance. Most often, gardeners are faced with the appearance of gray mold, which develops with a combination of high humidity and poor ventilation.
If you notice a fluffy coating, you must immediately remove the affected bulbs, wipe the rest with a solution of potassium permanganate or fungicide and replace the packaging. There may also be a problem with thrips, which, when the temperature rises above +10 degrees, come out of torpor and begin to feed on the juice of the bulbs.
Another problem may be uneven cooling. Closer to the wall of the refrigerator, the temperature may drop below zero, which will lead to freezing of the onion tissue. Place the containers away from the back wall and the fan.
Regularly, every 2-3 weeks, inspect the planting material. This will allow you to identify problems in time and save the harvest.
FAQ: Frequently asked questions
Can gladioli be stored in the freezer?
No, absolutely not. Freezer temperatures (-18°C or lower) will kill the living tissue of the bulb, turning it into ice. After defrosting, they will turn into mush and rot.
Is it necessary to dust the bulbs with ash before storage?
Yes, wood ash is an excellent natural antiseptic and adsorbent. It dries out the cuts and creates an alkaline environment that is unfavorable for the development of fungi.
What to do if the bulbs begin to sprout in the refrigerator?
If the sprouts are white and small (up to 1 cm), this is not a problem, they can be carefully broken off. If the sprouts turn green and stretch out, it means the storage temperature was too high. It is better to plant such bulbs as seedlings or in a pot, since they have already used up some of their strength.
How often should you ventilate the container in the refrigerator?
It is enough to open the container or bag once every 2-3 weeks during a routine inspection. If the packaging is made correctly (with perforation or from breathable materials), frequent ventilation is not required.