The African milk tree (Euphorbia trigona) is native to Central Africa. This plant looks a lot like a cactus—hence its nicknames: candelabra cactus, cathedral cactus, friendship cactus, and good luck cactus—but it is actually a succulent plant. It features triangular stems, with three distinct sides seamed with ridges. The ridges are peppered with thorns and teardrop-shaped leaves. This plant stays lush and green throughout its growing season, with new growth sprouting a light green hue.
Like a cactus, the African milk tree is a long-lived plant that grows vigorously, approximately 1 to 2 feet a year up to 9 feet tall. It is often grown as a hedge due to its rapid and enthusiastic growth. When grown indoors, this plant will only grow to about half of its maximum height.
The African milk plant (Synadenium grantii) is an interesting houseplant that originates from tropical Africa. This unique plant is loved for its eye-catching foliage and easy care requirements. An added benefit of the African milk plant is that it can be easily propagated from seeds. In this comprehensive guide we’ll look at everything you need to know about African milk plant seeds including germination storage and sowing techniques.
Before we dive into seed specifics let’s start with a quick overview of this fascinating plant. The African milk plant is known by several common names including African milk bush Euphorbia trigona, and cathedral cactus. It features succulent, triangular stems with small leaves growing in pairs along the ridges. The stems exude a milky sap when damaged.
One of the most distinctive features of the African milk plant is its natural, tree-like shape with multiple branches stemming from the base. It has an upright, candelabra-like growth habit. In the right conditions, this hardy plant can reach heights of 9 feet tall!
Germinating African Milk Plant Seeds
Germination is the process of seeds sprouting and the embryo emerging. Understanding optimal techniques for germinating African milk plant seeds is key for success. There are two primary methods:
Water Germination
This technique involves:
- Soak seeds in room temperature water for 24 hours. This hydrates the seeds and initiates germination.
- Transfer the soaked seeds to damp paper towels and seal in a plastic bag. Store the bag in a warm area (65-75°F).
- Check seeds daily and keep the paper towels moist. Sprouting typically occurs within 5-7 days.
- Once sprouted, plant the seeds in starter soil mix. Water lightly and provide ample warmth and light.
Direct Soil Planting
This method entails:
- Fill starter pots with well-draining potting mix. Moisten the soil.
- Gently press 1-2 seeds just below the soil surface in each pot.
- Cover pots with plastic to retain moisture and warmth.
- Check pots daily and water soil as needed to maintain dampness.
- Remove plastic once seedlings emerge in 5-7 days. Provide light.
Soil planting avoids potential mold issues that can accompany paper towel germination. However, it can be harder to monitor seed progress.
Storing African Milk Plant Seeds
If you want to save African milk plant seeds for future planting, proper storage is vital for maintaining viability. Here are some tips:
- Collect seeds from ripe seed pods once they naturally split open. Remove any debris.
- Allow fresh seeds to fully dry for 1-2 weeks in a cool, dry spot.
- Place dried seeds in an airtight container such as a plastic bag or glass jar.
- Store in refrigerator (not freezer).Viability lasts for several years when refrigerated.
- Clearly label containers with seed type and year collected.
Improper storage leads to mold, premature sprouting, and loss of viability. Proper techniques ensure your seeds stay viable for future use.
Sowing African Milk Plant Seeds Outdoors
Sowing refers to planting seeds directly in the garden. Here is an overview of sowing African milk plant seeds outdoors:
Location – Select a site with full sun to partial shade with well-draining soil. Protect from heavy winds.
Soil Prep – Loosen soil and mix in organic compost. Remove any weeds.
Planting Time – Sow seeds outdoors after the final spring frost when temperatures warm.
Planting Depth – Sow seeds 1⁄4-1⁄2 inch deep in prepared soil. Space seeds 12-18 inches apart.
Watering – Water newly planted seeds daily to maintain consistent moisture. Reduce frequency after seedlings emerge.
Thinning – Thin overcrowded seedlings to the strongest plant every 18-24 inches once established.
With proper sowing techniques, you can successfully grow African milk plants from seeds in the garden. Be sure to handle seeds carefully due to the toxic, milky sap.
Common Questions About African Milk Plant Seeds
Growing African milk plants from seeds does have some unique considerations. Here are answers to some frequently asked questions:
How long does it take for seeds to germinate?
In optimal conditions, germination typically occurs within 5-7 days. Seeds can take 10-15 days to sprout in cooler temperatures.
When is the best time to harvest seeds?
Collect seeds once the pods naturally split open and release seeds. This occurs in late summer to fall in mature plants.
How long are seeds viable for?
Stored properly, African milk plant seeds remain viable for 2-5 years. Viability gradually declines over time.
Can you grow African milk plant seeds in water?
Yes, water germination is an effective technique. Be sure to change the water every 2-3 days to prevent mold growth.
How can you tell if seeds are no longer viable?
Seeds that are soft, moldy, discolored, or dried out are no longer viable. Low or no germination rates also indicate unviable seeds.
Key Takeaways on African Milk Plant Seeds
Potting and Repotting African Milk Tree
Providing ample drainage and not overwatering are important considerations when potting African milk tree. This succulent will do best in a porous clay pot that absorbs excess water. Avoid glazed pots that add to the risk of overwatering. Sandy soil or potting mix formulated specifically for succulents allows for the best water drainage, especially when pumice or perlite is mixed in.
Repot the plant every year or two as it continues to grow taller. This will ensure that theres enough room for the roots to hold it in place (with a little help from stakes). Always wear gloves and note that it may take two people to repot a large plant, assuring a damage-free process.
Propagating African Milk Tree
African milk tree propagates easily from cuttings. Due to the plants toxicity, use proper protective gear when propagating—like heavy gloves—and wash your hands immediately if you get the milky sap on your skin.
Heres how to propagate African milk tree from cuttings:
- Gather a sharp knife or hand pruners, alcohol wipes, a 4-inch container with potting medium, and coarse gravel.
- Sterilize the blades of your knife or scissors with alcohol, and then cut off one of the plants “arms” at its base.
- Rinse the arm with cold running water until it stops oozing.
- Let the arm sit in a dry spot on a paper towel, out of direct sunlight, for five to seven days, allowing the cut tip to callus over. (Note: Many growers bypass the callus stage and put the cutting directly into the soil. Root growth should occur within three weeks using this method, but it also makes the plant susceptible to root rot.)
- Once the callus has formed, plant the arm in your container so that the end sits about an inch below the soil.
- Add a layer of gravel on top of the soil to help keep the cutting upright.
- Place the pot in a warm area with sufficient light and a temperature between 65 and 75 F, but out of direct sunlight. The cutting should root within two months.
- As soon as you see root growth, transplant the plant into a slightly larger, 6-inch pot.