Garden Republic's Guide to Bonsai Seed Sowing and Care

July 30, 2021

Garden Republic's Guide to Bonsai Seed Sowing and Care

Do you have our Bonsai Bonanza Starter Kit or our 8-variety Bonsai Seed set? If so, this is the article for you! 

It would be nice if all the seeds in existence would make it easy on us, and have the same growing requirements. Unfortunately, this isn't the case. Seeds come from all different locations, climates, and may have special stratification methods to ensure germination. 

Growing a tree from seed requires patience and lots of TLC, keep in mind you are growing a tree! There will always be trial and error, especially if you are just starting on your Bonsai growing adventure. This is your all-in-one, get down to the nitty-gritty, how-to-guide to best sow and care for your bonsai seeds!

*Helpful Note: If the titles/names of the tree seeds are highlighted in green, click on it, and it will take you to a how-to video (thank you Nikki!) for that seed!
*If the title/name is highlighted in blue, click on it and it will take you to the a more-in depth article on the topic, or a product page!

 

Give the seed packets a good read!
The back of the seed packets contains crucial information, specific to each seed. Pay attention to the germination days ( how long it takes that seed variety to sprout on average), and the soil temperature required for that seeds. The seeds must be kept consistently kept at that temperature during the whole germination period, or they will struggle to pop up! A seed heating mat will be your best friend when it comes to keeping the soil warm.

 

Seed Specific Sowing and Care Information 
Bonsai seeds will need to be "prepared" before sowing in the soil. Stratification is an important step! This is done by soaking the seeds in water, or placing them between layers of wet paper towel, and soaking them. Again, different seeds will have their own unique needs!

Flame Tree (Delonix Regia)

  1. These seeds have a SUPER hard shell casing. You can help the seed sprout easier by soaking them in warm water for 24-48 hours. Keeping water/seeds in an insulated mug while soaking will help this process. Once they are done soaking, don't be surprised if they have a white membrane-like substance on the seed casing, this is normal!
  2. Once they are done soaking, grab a sturdy pair of scissors or small pruners, and snip 1/8th of the pointy end of the seed off. 
  3. Now you can plant the flame seeds in the soil! You'll want to so them lengthwise/sideways in the soil at a shallow depth, about 1/4"-1/2" deep. 
  4. You want to keep the soil between 70-80F, 75F being the sweet spot. They can take up to a month to germinate.
  5. Make sure you keep the soil moist, not soaking wet, and don't let it dry out! It's helpful to give the flame tree's soil a good misting every morning.

Brazillian Rosewood (Jacaranda Mimosifolia)

  1.  It's common for the paper-like part of the flat seed casing to arrive to you broken off, don't worry! This is just the part of the seed that would normally help it travel in nature, which isn't needed since we are planting them ourselves. So if your seeds look broken when they arrive, they are actually ok. 
  2. The best way to soak these fragile seeds is between sheets of wet paper towels. You can then place it in a shallow bowl with warm water, and soak them for 12-24 hours before planting. 
  3. Plant them in at a shallow depth in the soil, no deeper than 1/4"! You can lay them on top of the soil, and sprinkle leftover soil over the top of them until they are just barely covered. 
  4. Their name hints, they like it hot! Anything less than 85F is going to produce poor results if any. And keep in mind it can take these seeds almost two months to germinate. A seed heating mat will help you and your seed a lot. 
  5. Once they are mature, Rosewood is hardy to only 55*F and needs winter protection, so use caution during the winter months.

Colorado Blue Spruce (Picea Pungens Glauca San Juan), Black Spruce(Picea Mariana), Japanese Black Pine(Pinus Thunbergii)

  1. Start by giving these seeds an 8-12-hour soak in cool water. Any longer can rot the seeds! The seeds are pretty small, so draining the water into a strainer or coffee filter, then using tweezers to grab the seeds can help.
  2. Don't plant the seeds too deep in the soil, no deeper than 1/8th". Make sure the soil is nice and loose before planting, and don't pack the soil down after the seeds are sown.
  3. Keep the seeds in a cool location, away from hot sunshine and drafty windows and vents. They like their soil to stay at a cool 65F and can take a month to germinate.  
  4. The Spruces need to develop nice strong tap roots right away, so you will see only a couple inches of top growth during the first year. 

Dawn Redwood(Metasequoia Glyptostroboides)

  1. These seeds take a bit more preparation than the other seeds, but it must be done! Put a little bit of peat moss in a Ziploc bag then add the seeds. Place the bag in the crisper drawer in your refrigerator, and let them chill for a month. 
  2. After their winter trip, place them on top of the prepared soil, and lightly sprinkle soil over the seeds. They should be at a depth of 1/8th"-1/4th" Don't compress the soil too much!
  3. Put them in a bright, not hot location. They'll need to be kept at 70F, and can take two months to sprout!

Buddha Tree(Ficus Religiosa)

  1. Soak the seeds between wet paper towels for two days. Make sure you don't let them dry out! 
  2. After they are done soaking, take some sandpaper and rub each seed against it. You don't absolutely need to do this, but it will help spend up the extra-lenghty germination time!
  3. Nestle the seeds about 1/16" in the soil, you are barely even covering them! Mist the top of the soil when ever it drys out, and be carefull when deep-watering, you don't want to drive the seeds too deep in the soil.
  4. These seeds need to stay no cooler than 75F to germinate, and can take 90 days sprout, so have patience!
  5. It can help to place keep a loose-fitting piece of saran wrap over the top of the soil to keep the humidity in. Take the plastic on and off on alternating days. This can be done for the Brazilian Rosewood and Flame Tree as well.

Siberian Elm(Ulmus Pumila)

  1. Soak them in cold or warm water for a day. 
  2. Sow them in the soil no 1/4" or less. Very lightly compact the soil, just enough so they don't move when you water them. 
  3. They need to be keep cool, 65F-70F. They won't sprout if they get warmer than that. They can take about a month to germinate. 

Soil
Only use soil specifically for seed-starting when planting these seeds, and skip on using bonsai soil until they have matured and have a substantial root system. Using any other type of soil, other than seed starting soil, can result in poor germination. 

Watering
Monitor the average hydration of the soil, and make sure it stays damp but not soaking. Soaking wet soil can lead to rotten seeds, mold, and other undesirable soil conditions. All soils are different, so never rely on watering every day or on certain days. The water requirements for sprouts can vary from day to day, depending on their growth rate! You typically will do a deep watering a couple times a week, and mist the top soil whenever it looks dry. 

You can purchase a moisture meter or you can use a toothpick/wooden skewer. Carefully push the toothpick all the way into the soil. If it comes up wet/has soil stuck to it, you don't need to water. If it comes up dry/no soil stuck to it, you need to water.

Light
As soon as your seeds have sprouted, they will need lots of light to continue to grow past the cotyledon stage! If you're using an LED grow light, you'll need to make sure that it runs for at least 10 hours a day. If you're using a conventional "bulb-type" grow light, you can run it from 8-10 hours. Failure to supply your sprouts with enough sunshine will deprive them of their primary source of energy.
If you're relying on the light of the sun to get your sprouts to thrive, be prepared for temperamental little plant babies on cloudy days.  The cooler varieties( spruces, pine, elm, redwood)  won't like hot sunlight/grow lights, so may sure they get plenty of light, but stay nice and cool.

*If you are using a windowsill/natural sunlight to grow your sprouts, rotate the pots daily to help them grow straight and not leaning to one side!

Plant Food
Once your sprouts have developed their second set of leaves, they'll be getting hungry. It's time for plant food! A water-based, low-dose organic plant food is the best route to go, as this will reach the roots the easiest. Make sure it low in nitrogen, and has lots of micro-nutrients. 

Thinning out your sprouts:
For the strongest, healthiest sprouts, you'll want just one seedling per pot or cell.  Thinning is challenging for many gardeners; who wants to destroy sprouts you've worked so hard to grow?! But it has to be done. Select the strongest, healthiest seedling and use a pair of scissors to snip off the others at the soil line. You can try to transplant the extras into different pots, but you risk disturbing the roots too much and killing them all!

Transplanting (click for video)
Although it can be super tempting, give your sprouts time to grow before putting them in a bonsai pot. Some sprouts can stay in the starter pots for up to a year! Replanting too soon can disturb the tender roots and kill your sprout. You can read our guide on when and how to transplant here. 

Have a sick bonsai tree or have questions?
If you have questions at any point about the sowing, growing, and caring process, don't hesitate to reach out! We are here to help and love to help new gardeners achieve optimum success with our seeds! We care! our email is wecare@shopgardenrepublic.com. You can also find us on Facebook and Instagram

Happy Tree Sowing! 


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