To properly store acorns, you must create the right conditions to keep them fresh and viable. The rules differ based on whether you intend to eat or plant them.
The most important rule for every type of acorn storage is to try to store only healthy acorns that don’t show signs of damage, such as mold rot or worms. Always take time to separate non-viable acorns during collection and processing to keep them away from your healthy batch.
Storing Acorns for Consumption
Storing the acorns is actually the easiest part. The preparation before storage is the process that requires the most attention.
Dry the acorns
The goal of preparing acorns for storage is to remove any moisture that could create rot and mold during storage. In other words, you need to dry them. We have a good tutorial on how to dry acorns using different methods.
Keeping the shell is essential to storing acorns
Dry acorns need their shells intact to prevent spoilage. Never remove the shell from the acorns you intend to store for consumption at any point during or after the drying process until you are ready to use them. The shells serve as natural preservatives.
Put them in an airtight container
After drying, place the acorns in an airtight container and keep them away from direct sunlight in a cool place. This will help prevent mold growth and preserve the quality of your acorns for a longer time.
If you plan to use your acorns for cooking, you may also want to consider vacuum sealing them to extend their shelf life even further.
How long do acorns stay suitable for consumption?
A dried acorn will remain perfectly safe for consumption for several years if properly stored. However, giving yourself a window of 12 months to consume your acorns will assure you that they are still fresh and safe.
Can you freeze acorns?
Due to the number of people asking us this question, I decided to address it here. While freezing acorns isn’t popular, it is possible. Freezing will keep your acorns fresh until you have time to process them. So, if you really want to do it, remember to do it as a first step. My advice is that you dry them immediately. They will last a long time.
Storing Acorns for Planting
Storing acorns for planting later is different from saving them for consumption. In this case, you want to ensure you only get good acorns. We’ve already covered tips for foraging acorns that are likely to be viable and fruitful. That blog post will be a great addition to your research.
Also, when you mean to plant them, you should have different bags with labels for each acorn species; in case you have several. This is because some acorn species may sprout at slightly different times and temperatures. Additionally, you won’t confuse them by mixing a variety of species. You should know which oak species you are planting on a specific spot.
After making sure you only have viable acorns and that they are correctly sorted, follow one of the following storage methods.
Storing them in the fridge
Start by removing the caps; they should twist off easily when the acorns are ripe. Rinse all of the acorns in lukewarm water. If you are concerned about mold growth, you can add a drop of bleach to disinfect the acorns.
Allow the newly washed acorns to air dry on a towel. Once they are dried, pack them into plastic zip-lock bags.
Place the acorns in the refrigerator until you are ready to plant them. Generally, the limit to keeping acorns in the fridge is three to six months. Be sure to check periodically for any signs of mold.
If your acorns develop mold, you can rinse them off. After that, return them to the refrigerator in a dry bag.
Look out for premature germination
The cold temperature and lack of moisture will slow down the germination process. But acorns can still germinate prematurely in the fridge. This is a common problem with blue oak acorns.
If you let a couple of weeks pass after germination, they will start to rot. So, check your acorns occasionally, and if you see that a few have begun to germinate, plant them immediately.
Don’t let the acorns freeze
Make sure you don’t let the acorns freeze. After exposure to such low temperatures, the acorn will die and won’t be suitable for planting anymore.
This method will allow you to store your acorns for up to four months, as long as you keep the surrounding temperature cool and stable.
Put your acorns into a half-gallon zip-lock bag without crowding them. You can use several bags if you have a large batch. Next, add two to three cups of vermiculite.
Vermiculite is a hydrous phyllosilicate mineral that expands when heated. You can find it at any hardware store or garden center. Vermiculite is very useful in seed propagation because it helps to retain nutrients.
Every few weeks, check for the presence of mold. You can wash and repackage your acorns if you detect mold.
Whether you plan to consume or plant your acorns, proper storage is essential to ensure they remain viable and healthy.
Storing acorns for consumption is quite simple. It’s enough to dry them and keep them in a cool, dry place.
But if you want to plant an oak tree, storing your acorns will require more care. You have to pay attention to some details, such as moisture, temperature, and early germination. You can use several methods, such as storing them in the fridge or using vermiculite.