yoderjac
Well-Known Member
I tried making my own from shelving material from lowes. They worked just as well as the 18s, but I found them even more sensitive to watering than 18s.
Chestnut Production?
- Thread starter KSQ2
- Start date
I have a bunch of air pots propagation cells, that I'm going to get back to using as well. I got planting ADHD, and went to rootmakers, and just let the air pots sit. It's easier to get the seeding out of the airpot vs the RM18.
www.hydrofarm.com
Shop – Air-Pot®
air-pot.com
Air-Pot Container Propagation Cell (0.3 gal/1 L), case of 25
Air-Pot Prop Cell 0.3 Gal
yoderjac
Well-Known Member
I've never had an issue getting trees out of 18s. I use the express trays, not the old brittle plastic cells. I simply remove the cell and submerge it in water. I then put my hand across the top with the trunk between my fingers, invert it, and give it a good shake. Presuming the roots have properly filled the cell, it pops right out with all the media intact.I have a bunch of air pots propagation cells, that I'm going to get back to using as well. I got planting ADHD, and went to rootmakers, and just let the air pots sit. It's easier to get the seeding out of the airpot vs the RM18.
Shop – Air-Pot®
air-pot.com
Air-Pot Container Propagation Cell (0.3 gal/1 L), case of 25
Air-Pot Prop Cell 0.3 Gal
I do agree that the old brittle plastic type of 18s were much harder to extract trees from. One reason I like the RB2s for larger containers is how easy it is to unwrap them for extraction.
KSQ2
Well-Known Member
I’ve used 1 gallon, hard sided, root makers with oaks very successfully; chestnuts, not so much. Do you use bags?
KSQ2
Well-Known Member
Thanks everyone, lots of good info here. I need to find some nuts to buy this fall and I’ll get started next spring. If any of you are going to selling chestnuts later this year, please let me know. I bought some from Matt last time, I’m not sure if he’s gonna be selling again. After reading this, I see I didn’t give the nuts he sold me much of a chance. I did a lot wrong. Oaks must be a lot more hardy in the pot growing process. I grew this 3 chestnuts behind the house earlier in this thread from seed, but I think I used miracle grow potting souls in those in the one gallon root makers 10 years ago, I skipped the potting soil last time around.
yoderjac
Well-Known Member
I've tried root trapper bags, but I prefer the Rootbuilder II containers like these:
They can be held in place with plastic rings which work well and can be reused, or cable ties. You can see how they easily unwrap for easy planting.
Here is what the 1 gal containers look like before assembly:
You wrap them around the base and clip them with the rings. When it is time to plant, you open the rings and unwrap them like the top picture.
These containers can be use year after year. The bags seem to wear out.
I finished with trees a couple years ago and moved on to other projects. I got a little over $1,000 for all my used rootmaker stuff.
yoderjac
Well-Known Member
By the way, I avoid potting soil like miracle grow and similar mixes for rootmakers. They are too fine and hold water too long for chestnuts. With rootmakers you want a chunkier mix like Promix. It works better for soaking and letting chestnuts dry out. The voids in the mix give the many lateral root tips created by root pruning a place to fill.
This is not to say, you can't uses potting soil or even native soil. Trees can do amazing things under harsh conditions. I'm just talking about best practices to maximize growth and give your seedlings the best chance.
Here is a quick summary on the root pruning technique for those new to this:
Dr. Witcomb was the primary pioneer in this technique and he has some good articles you can read, but here is a short description. There are several methods that can be use for root pruning, air pruning, root trapping, and root constriction. Rootmaker makes containers for all of these. For my purposes, I found air pruning to be the best fit for my situation.
Nutrients and water are taken up by the tree by the fine terminal roots. The more of these fine root tips, the more water and nutrients a tree can uptake. In nature, a seedling sacrifices growth early on putting a lot of energy into producing a deep tap root. It does this so that it can get access to water when the top layer of soil dries out. This means it puts less energy into producing fine root tips and producing top growth.
With root pruning, we are making a trade-off. When we prune the tap root, it forces the tree to do upstream branching. Most of this occurs in the first 4" of the prune. With air pruning, 18s are designed to force roots downward to holes in the bottom of the container. The cells are elevated so there is good air flow below the container. When the tap root hits the air, it desiccates which forces upstream branching. These lateral branches grow outward until they hit the angled container walls and are forced down to wholes where they are pruned. They too then have upstream branching and so on.
Since we are providing water and nutrients, all these additional terminal root tips uptake more nutrients. Since the tree can't put energy into the tap root, it puts more energy into both top growth and lateral branching. We thus get much faster growth, but we need to provide the nutrients and water.
When the 18s are filled with roots, we transplant to the 1 or 3 gal containers. I like to use both, but some go directly to 3 gal. When you try to plant from a smaller container, although the seedling is larger the root system is not very deep. While the root system is dense and very efficient, it can only uptake what it can reach. When the top layer of soil dries out the tree is in trouble unless you are providing supplemental water. The depth of the final container is dependent on how much your soil dries out and for how long if you don't provide water.
In my area 3 gal is deep enough given our climate. Keep in mind that if you are in an area that is more arid, root pruning may not be the best option. Direct seeding may be a better option. Growth will be slower, but a deep tap root ensures survival during long dry periods.
This is not to say, you can't uses potting soil or even native soil. Trees can do amazing things under harsh conditions. I'm just talking about best practices to maximize growth and give your seedlings the best chance.
Here is a quick summary on the root pruning technique for those new to this:
Dr. Witcomb was the primary pioneer in this technique and he has some good articles you can read, but here is a short description. There are several methods that can be use for root pruning, air pruning, root trapping, and root constriction. Rootmaker makes containers for all of these. For my purposes, I found air pruning to be the best fit for my situation.
Nutrients and water are taken up by the tree by the fine terminal roots. The more of these fine root tips, the more water and nutrients a tree can uptake. In nature, a seedling sacrifices growth early on putting a lot of energy into producing a deep tap root. It does this so that it can get access to water when the top layer of soil dries out. This means it puts less energy into producing fine root tips and producing top growth.
With root pruning, we are making a trade-off. When we prune the tap root, it forces the tree to do upstream branching. Most of this occurs in the first 4" of the prune. With air pruning, 18s are designed to force roots downward to holes in the bottom of the container. The cells are elevated so there is good air flow below the container. When the tap root hits the air, it desiccates which forces upstream branching. These lateral branches grow outward until they hit the angled container walls and are forced down to wholes where they are pruned. They too then have upstream branching and so on.
Since we are providing water and nutrients, all these additional terminal root tips uptake more nutrients. Since the tree can't put energy into the tap root, it puts more energy into both top growth and lateral branching. We thus get much faster growth, but we need to provide the nutrients and water.
When the 18s are filled with roots, we transplant to the 1 or 3 gal containers. I like to use both, but some go directly to 3 gal. When you try to plant from a smaller container, although the seedling is larger the root system is not very deep. While the root system is dense and very efficient, it can only uptake what it can reach. When the top layer of soil dries out the tree is in trouble unless you are providing supplemental water. The depth of the final container is dependent on how much your soil dries out and for how long if you don't provide water.
In my area 3 gal is deep enough given our climate. Keep in mind that if you are in an area that is more arid, root pruning may not be the best option. Direct seeding may be a better option. Growth will be slower, but a deep tap root ensures survival during long dry periods.
yoderjac
Well-Known Member
If you want to maximize growth, you need to start with 18s to get that tap root pruned early and then transplant to 1 gal and 3 gal. The hard sided rootmaker pots work fine for the second stage. It is just a bit harder to extract them for transplant than it is with the RB2 containers.
yoderjac
Well-Known Member
Yes, growing season makes a difference. Even down here in zone 7a, I would start my trees indoors under lights in the winter. While it was primarily a "cabin fever" project for winter, it also extends that first growing season quite a bit. My seedlings were about 10-12 inches tall when I transplant to 1 gal RB2s and move them outside. My direct seeded nuts are just beginning to emerge.
KSQ2
Well-Known Member
The Mrs has some grow lights for her indoor plants; when do you start your chestnuts? Do they need to cold stratify first?
KSQ2
Well-Known Member
Do these need to be suspended on a tray or something?I have a bunch of air pots propagation cells, that I'm going to get back to using as well. I got planting ADHD, and went to rootmakers, and just let the air pots sit. It's easier to get the seeding out of the airpot vs the RM18.
Shop – Air-Pot®
air-pot.com
Air-Pot Container Propagation Cell (0.3 gal/1 L), case of 25
Air-Pot Prop Cell 0.3 Gal
yoderjac
Well-Known Member
Yes, they need to cold stratify first. I do that in the crisper of the fridge. Getting moisture right is critical. Too little and they won't stratify. To much and you will get mold. My last threat of frost here is mid-April. I figure about 16 weeks in 18s, so I back off that mid-April date by about 16 weeks so I'm transplanting to 1 gals about the time I begin to acclimate them to the outdoors.
I use cheap fluorescent shop lights. No fancy grow light needed. Now a days, you can get LED lights for shop lights. I like them because you can hang them at an angle and sort your trees by height in express trays.
The amount of time you cold stratify makes a difference in germination rates. Wayne and I did a test one year where we did everything the same but cold stratified for different periods. I'll see if I can dig up the graph for that. I simply started with many more nuts than I needed to compensate for lower germination rates for the shorter stratification periods.
Don't try to start them in a southern facing window. That produces a poor root system even though they look good above ground. Dr. Whitcomb warns against this. You need to use artificial light. Light energy diminishes with the distance squared. You need to adjust the lights so they are only a few inches above the trees. LEDs are great because they are even cooler than fluorescent bulbs so you can hang them closer.
Care must be taken when acclimating them to sun in the spring. You have to do it slowly. I have a lower deck that is shaded from all but early morning sun. I start them there and eventually move them to my upper deck which gets full morning sun but is shaded from the harsh afternoon sun.
Hope this helps.
yoderjac
Well-Known Member
I can't speak to some of the other brands. Some do a better job of supporting the basic principles of root pruning than others. I will say that the rootbuilder II pots have bottoms that are convex into the container and have ridges. They can sit on your deck or floor. The bottoms are designed to direct lateral roots outward to the lower holes in the sides. I notice that some of the off brands of containers have protrusions that stick out horizontally. If you look at the RB2 sides, the protrusions are directional directing roots down and out.
I haven't done any comparison between different brands of containers, but I do know from reports of others that some don't work as well and others work just fine.
I will say that you need some way to keep medium in the bottom of larger containers. Watering will eventually erode the bottom of the media out if you don't. I will also say that you want air flow anywhere the roots exit the container for air pruning.
KSQ2
Well-Known Member
I’ve had pretty good luck with cold stratifying in the back fridge. Usually an open ziplock with a mildly damp paper towel. I’d really appreciate it if you could find that info on stratifying length of time.
KSQ2
Well-Known Member
Don’t you guys use gravel in the bottom of the 3 gallon containers? Or am I dreaming that?
yoderjac
Well-Known Member
There charts came from the year Wayne and I did the comparison. The year Wayne (wpdeer) and I did a test where we handled our chestnuts pretty much the same but he cold stratified for close to 90 days and mine were about 60 days. My germination rate was in the 70s% and his was well into the 90s%.
yoderjac
Well-Known Member
I use quarry stone when I plant but I don't use gravel in any of my containers. There is a technique called a Missouri Gravel Bed that you can query. I considered going that route rather than using containers, but I was already invested in containers. If I was younger at the time and wanted to operate at a larger scale, I would have considered using it instead.
