How To Grow Pawpaws From Seed (>90% Germination Rate)

Look, I’m going to cut to the chase. I’ve been growing Pawpaw trees from seed for several years, and have refined my methods to achieve germination rates above 90%. I will show you exactly what to do, to germinate and grow Pawpaws from seed. All pictures in this article are my own.

You’re not going to find a better source on the web for this, and all pictures in this article are my own. My germination rates are above 90%, and yours can be too. But in this guide I’m going to cover how to gather, sterilize, and store the seed. Then, I will cover the methods you can use to break dormancy and plant them. Finally I will go through my own process, as I am pulling ripe pawpaw seeds from ones I forage to germination the following year.

Pawpaw Trees

Since common names of plants can sometimes cause confusion, please know that the tree I call the Pawpaw is scientifically known as Asimina triloba. It is native to North America, from Texas to Florida and North to Michigan, New York, and Southern Ontario. If you would like to know more of the ‘nitty gritty’ details you can read my profile on Pawpaw Trees^[1][2].

Gather seed from ripe pawpaws

Seed can be gathered from ripe Pawpaw trees in late Summer or early Fall. And when I say ‘ripe’ Pawpaws, I mean it. You want the seed to come from pawpaws that are naturally falling from the tree, as that way you know the seed should be fully developed.

If you gather Pawpaws before they are ripe, the seed inside has not had time to fully mature. The viability of the seed will be lower than that of a seed from a fully ripe pawpaw.

Determining if pawpaws are ripe

Pawpaws are ripe when they naturally fall from the tree. But since most of us don’t have Pawpaw trees in their backyard, you may not have the opportunity to wait around for them to begin falling.

However, you can employ my method to know if they are ripe when I forage. Simply shake the tree in a gentle manner, and if pawpaws are ripe, they will fall. If you violently shake the tree, more pawpaws will surely fall, but they will not always be ripe. And if a pawpaw is taken too early from a tree it may never fully ripen.

Harvesting seed from pawpaws

To get the seed, simply cut the pawpaw in half lengthwise using a paring or steak knife. Then, pop the seeds out from the Pawpaw. The seeds often have a thin film on them that will be quite slippery, and is attached at the base of the seed. I personally like to remove this with my knife. But since the coating is slippery, be careful when doing so.

Sterilizing pawpaw seed

Once you have the seed out, give it a quick rinse in water. Then, soak the seed in a 10% bleach/water solution for a minute. After one minute, remove from the solution and rinse again under tap water.

This step will sterilize the pawpaw seed and kill any fungus. After this, you can either store the seed, plant it, or cold stratify it in the refrigerator.

Storing seed

Pawpaw seed can be stored for some years without losing much viability. The University of Kentucky found that Pawpaw seeds remain viable for several years when stored in a sealed container under refrigeration^[3]. So, you can use any air-tight container to store your seeds in the fridge. I have never stored mine more than a few months before sowing them, and usually just use a zip-lock bag.

Cold stratification

Pawpaw seeds have a dormancy mechanism that will prevent them from germinating. To overcome this, the seed must experience a period of cold-moist stratification. The USDA and other researchers recommend 120 days^[4][5], which also matches my experience.

To achieve the cold stratification, you either need to Winter Sow or use the refrigerator. Below I will discuss stratifying in the refrigerator first:

Cold stratifying in the fridge using sand

You can do this by mixing up sand and sphagnum peat moss in a 80/20 mix, and moistening it. The final mixture should be wet enough that when you squeeze it with your hand only a few drops of water fall out. Place a layer of this mixture in a sealable container or plastic bag, then lay your seeds on top of it. Then, put another layer 1-2″ deep of the moist sand on top, and seal the container. Label it, then place it in the fridge for approximately four months or until early Spring. At that point you can plant your seeds 1-2″ deep in containers or in the ground at a location with appropriate growing conditions.

Cold stratifying in the refrigerator using moist paper towels

Normally you would want to use sand to stratify pawpaw seeds, as the large seed size makes it difficult to keep from drying out using paper towels. But I have made a modified method that work.

First, you use two full sheet paper towels, water, and a zip-lock bag. Lay both paper towels down on a clean surface, and spray with water. You want the paper towel to get moist enough so that when you squeeze it a few drops of water fall out. Once you’ve done this, lay out one towel flat and open on a clean surface. Then, place the second moist towel directly on top.

Next you will place your pawpaw seeds in one quadrant of the towel, then fold it three times so that the seeds are completely surrounded by several layers of paper towel. Place the folded up moist towel in a ziplock bag and seal it. Then, as you probably guessed, you just label it and store it in the refrigerator for 120 days.

Winter sowing pawpaw seeds

To winter sow papaws, we will let mother nature do the cold stratifying for us. It is very easy, simply plant your seeds 1-2″ deep^[5] in a container that can hold at least six inches of soil (Pawpaw trees have a taproot and need the space right away after germinating).

Place your container in a location that will be exposed to cool temperatures, yet protected from the coldest parts of the winter. An unheated garage or shed typically works great for this, as you can also monitor to make sure the soil doesn’t completely dry out. I like to give a small amount of water to each of my pots once a week.

Once spring approaches and the chances of prolonged freezing have passed, move the containers outside to a location that gets morning sun and afternoon shade. Germination will occur in mid-summer, usually around the first week of July for me in zone 6 (Southern Pennsylvania).

My method to germinate and grow Pawpaws from seed

Ok, so the way I have had the highest success in germinating Pawpaws is to do a combination of cold moist stratification and winter sowing. What I do is to harvest and sterilize the seed as described above, and then start cold stratifying it in the fridge (usually in September/October).

1 – Harvesting seed from fresh Pawpaws

I collect seed from pawpaws as I eat them. I pop them out with a knife, or I spit them out onto a plate while eating them. After I’ve eaten my pawpaw, I remove the slippery coating with a knife or my fingernail.

I will soak them in a 10% bleach and water solution for a minute. Then, simply rinse them under tap water. It can be helpful to use a colander or strainer to do this step.

2 – Storing & stratifying seed

If I’m not planning to plant the seed that winter, then I will simply place them in a zip-lock bag and store them in the fridge with the year of harvest. But if I plan to grow those trees the following Spring, I will begin cold stratifying them immediately.

As I mentioned before, you can cold stratify the seed using moist sand or paper towels. I tend to use two full-sheet paper towels with 10-30 pawpaw seeds. The first step is to thoroughly moisten both paper towels. Since you’ve sterilized your seed, then the chances of having fungus or mold form is low, so you can get them really wet if you like.

So, my stratification method prior to winter sowing goes like this:

• Fold one full-sheet paper towel in half and lay your pawpaw seeds on half. Then, fold it over and spray it with a water until thoroughly moist.
  • 
• Lay the other full sheet paper towel down, and place the first one in the center.
  • 
• Fold the paper towel around the first that contains the seeds. This is sort of like ‘wrapping it up’.
• Squirt the second paper towel with water until it is moistened.
  • 
• Place in a 1-quart zip-lock bag and label. Then place in the refrigerator until ready to winter sow
  • 

I made an infographic below that shows the entire process. Click on the image for a pdf.

3 – Planting, winter storing

I generally winter sow all my seeds around Christmas, or early January and Pawpaws are no exception. Since I begin the stratification in the previous step, it is ok for me to wait. Otherwise, you could just plant them in late Summer/Fall when you eat them.

For planting pawpaw seeds, you want to use a deep container. I like to use 14″ deep pots, but 6″ should be the minimum. You need to do this because Pawpaws produce a taproot, and you want this to have room to grow down into the pot.

The planting depth of Pawpaw seeds is 1-2″ deep. I like to fill my pots with moist potting soil, leaving about 3″ from the top. Then I just lay the pawpaw seeds on top of the soil, then cover with 1-2″, leaving a 1″ gap at the top. Press the soil firm.

Where to place your containers

Pawpaw seeds need 120 days of cold-moist conditions before they germinate. But, they cannot be frozen or else the seed will die. I learned this the hard way one year where we had several weeks of freezing temperatures – as in the temperature never got above freezing! And, back in 2022 I had a number of containers along the north side of my home with pawpaw seeds. Well, the pots turned into giant ice cubes, and the following summer I got zero germination. Lesson learned.

So where should you store winter sown pawpaws? Easy – the garage or shed during the coldest parts of the winter. This will generally prevent the seeds from freezing, but still allow the cold treatment. And that is exactly what I do now when sowing pawpaw seeds – I keep them in my garage.

Now, they don’t require much maintenance during the winter so to speak, but don’t let the soil completely dry out. You should plan on giving each container a small amount of water once per week. I do this on Sunday mornings and it just sort of becomes routine.

The amount of water you need won’t be much, but will take some ‘testing’. Just pick up the container each week and if it is feeling light, then you probably need to give it more water than you have been.

When to take winter sown pawpaw containers outside

As Spring approaches, I will take my containers outside to the North East side of my home. This allows them to get morning sun, and afternoon shade. If you place them in the sun all day long, they will just need more water. Pawpaws are very slow to germinate and patience is required.

I will water the containers (along with all my other seedlings) as needed so they don’t fully dry out. Again, just pick up a container periodically to see if it is heavy or not. If it feels light, it needs water.

4 – Germination

Pawpaw seeds take a really long time to germinate. In my years of growing Pawpaw seeds, I’ve never had them germinate prior to July. That’s right – July. For reference, I’m in Southern Pennsylvania.

Pawpaw seeds are incredibly slow to germinate. I mean, really, really slow. And you may have heard people say that Pawpaws are hard to grow from seed, and if you’ve made this far, you can see that there is a bit of work involved. But, I believe that most people who fail at germinating Pawpaw seeds do so due to a lack of patience, or just not knowing that they will take so long to germinate.

Caring for seedlings

So, once Pawpaw seeds germinate, you can keep them in their location and just water them daily or as needed. They will grow up to 6″ by the first year. I will keep them in a container until Autumn, when I plant them out to their final location.

Transplanting seedlings

Look, I grow a lot of trees from seed, and I plant nearly all out to their final location in the Fall. It is the absolute best time to plant trees (including pawpaw trees). The cooler temperatures mean that there will not be much heat demand on the tree. And there is still plenty of time before Winter sets in for the root to grow further down.

Choosing the location

Location location location! For Pawpaws they are pretty adaptable in that they can grow in full sun or full shade. But moisture and drainage is what you truly want to consider. Pawpaw trees are not drought tolerant. They will require access to moisture, either by where you plant it or by supplemental water you provide.

The area I plant my trees is considered part-sun or full sun, but it gets shaded in the hottest parts of the afternoon. This is about the perfect place to grow Pawpaw trees. In my experience foraging, the more sun a pawpaw tree gets, then the larger pawpaws it will produce. While Pawpaws can grow in full shade, if they don’t get much sun then the pawpaws they produce are small – almost like a golf ball. While Pawpaw trees that grow along a road get southern exposure seem to produce 4-6″ long pawpaws that are several inches in diameter.

Protecting young trees

Pawpaw leaves, twigs, and bark are all toxic. And thus they don’t seem to be eaten by deer. However, young trees are at risk of being damaged by bucks rubbing their antlers on the bark to mark their territory during the rut. Because of that, I place tree shelters over all Pawpaw trees I plant. If you don’t have deer where you live, then you probably don’t need to place a shelter around the tree.

Conclusion

Growing Pawpaw trees from seed is a fun and rewarding experience. It takes a bit of work, but isn’t too complicated once you know what to do, which I hope I was able to teach you in this article. I do document this in a video, which I will link to below. I’ll timestamp it so that it will go straight to the part where I save the seed so you can skip the intro.

But I hope you found this helpful, and if so, please share it on your social media as that greatly helps me out, and I truly appreciate it.