Growing Catalpa Trees From Seed - Fall Pod Havesting - December 2021

In our backyard, we have a couple of mature (and a few smaller, understory) Catalpa trees.  I've posted about them from time-to-time and talked about how I've come around on them and have grown to really enjoy the species.  And how the Catalpa tree has become a sort-of gateway into the whole "Native Tree" world.  This Spring, we came across some Kentucky Coffee Tree seed pods at a Downers Grove park and successfully germinated them and grew some seedlings.   We're currently attempting to overwinter those tiny seedlings by digging their containers in the ground.  What I've learned from those seedlings was that the seeds required a winter rest.  Or...what they call stratification.  That means that they require a period of dormancy that comes along with the cold temperatures of Winter.  For the Kentucky Coffee tree, that happens with the seed pods hanging on the trees all Winter until Spring when they drop.  

Based on that experience, I've decided to try my hand at growing Catalpa trees from seed.  But, I'm actually unsure of how to go about it.  From what I've read, the Catalpa tree seeds are similar to the Kentucky Coffee Tree seeds in that it is best to keep the seeds in the pods all Winter.  But, what (at least for our yard) is different is that the Catalpa trees we have began to drop their seed pods already.  Not all of them.  But, some of them.

Thus, I'm taking an approach that is four-fold:

1.  Leaving the seed pods that are still on the tree to stay all Winter.  And, come late Winter/early Spring, collect the pods then.

2.  I've picked up the pods that fell and cracked them open to harvest the seeds.  Planting them in the ground RIGHT NOW to see if they'll germinate come Spring.

3.  Similar to #2, but instead of being in the ground, I'm going to put them in a container.  A large container.

4.  Collecting the seed pods that feel, but leaving them closed and simply storing the pods outside in a spot that seems like critters won't get to (in this case, under our patio furniture cover).  I'll then grab them when the weather turns Spring and plant them in small nursery pots similar to the Kentucky Coffee Tree seeds from last Spring.

The photos below show #2, #3 and #4.  First, a look at the pods and how they've turned light brown.  In my hand below is one pod that I cracked open.  And a few that I stuck on the table for winter storage.

Before I started this, I went on YouTube to try to figure out what the right thing to do is with Catalpas.  There doesn't seem to be a grower in my Northern USDA zone, but this guy on YouTube has a really nice video that shows off the steps.  That's also where I first was shown what the seeds actually are. They're these little white things with wings.  The seed is in the middle, but the 'wings' allow for the seed to scatter.  Kinda genius, right?  See below for some of the seeds that I pulled out of one half of the pod.  There are dozens of seeds in each long, slender seed pod:

As for my process for the #2 above (planting the seeds in the ground during Winter), here's a look at where I've decided to try to germinate some seedlings.  This is back against the fence, by my yard hydrant hose that is (currently) unplanted and mostly goes undisturbed during the Spring and Summer.  Below is the location where I moved the mulch.  Note the yard hydrant hanger to the right.  

I put a couple of seeds in each little trench that I dug. Below you can see the twelve-or-so seeds that I put down.  They're about six to eight inches from the fence.  And run from the 3rd full fence board from the hydrant to the eighth.

Once I laid down the seeds, I covered them back up with some soil and then raked the hardwood fine mulch back on top.  Will critters get to them?  I'm not sure.  But, that's why....

...I'm spreading out my bets.  That means planting a few seeds in this large container - a wine barrel planter that is in one of the beds of our backyard.  This planter has a couple of other tree seedlings that I've grown including a Northern Red Oak tree (on the top left with red-ish leaves) and what I'm pretty sure are a couple of American Elm seedlings that are volunteers.  The Catalpa seeds are in the trench on the middle/right and I scattered ten-or-so in here.

Will any of these produce seedlings?  I have no idea.  But, with the pods already off the tree, I figured it was worth a shot.  I'll have to update the blog with a post come Late Winter when I try to yank the remaining pods off the tree and give them a shot in small containers.   I suppose I should tag this post as part of my 2022 to-do list so I remember to revisit these seeds come Spring.