Propagating a Mugo Pine by Seed

Pinus mugo
http://en.wikipedia.org/wiki/Mountain_Pine

Introduction:

            The Mugo Pine (Pinus mugo) also known as the Swiss Mountain Pine is a very popular evergreen shrub used for landscaping (1). It is native to the mountains of central and southern Europe (1). Some of the wild types can grow to be 80 feet tall, but the most popular varieties are the dwarfs (1). However it is hard to propagate vegetatively. Propagation by seed is the best known method even though it can produce highly variable offspring.  Two good cultivars known to be used for seed propagation are the “Slowmound” and the “Mops” (1). The pine is a favorite choice for home security. Because of its size and the sharpness of the needles it is planted under windows to deter trespassers from breaking and entering (1).

Seed Propagation:

Propagation by seed is the primary way of regeneration for most woody plants (2). It allows for the recombination of genetic material from parents to offspring which results in variation, unlike cutting or clonal propagation. A seed forms when pollen fertilizes the ovule of the plant. There are three parts to a seed, the embryo, the seed coat, and the endosperm. The embryo is the immature plant that remains dormant until the proper conditions have been met (2). The seed coat is the hard outer covering that protects the embryo and endosperm inside of it. And the endosperm is stored food for the embryo that is rich in oil, fat, and protein (2). The seed of a pine like the Mugo Pine is found within a cone that is the female structure of the plant. Seeds stay dormant until conditions are optimal for growth. The key to seed propagation is to create those perfect conditions for the seed. Certain seeds need specific lengths of daylight, moisture, or they may need help breaking through their seed coat in order to germinate. Depending on what you are propagating you should have some knowledge of what the seeds need to overcome dormancy.

Anatomy of a Seed
http://biologyplantlife.wikispaces.com/Seed+Structure

Propagating the Mugo Pine by Seed:

·         Step 1: Find a seed distributor that will sell the specific variety that you want. Preferably dwarf cultivars that do not grow too slowly. Or if you already have a tree collect seed from the pine cones of the tree. An easy way to do that is to harvest the cones when they are ready, and shake, drop, or step on the cones to dislodge the amount of seed you want to use (3).  

·         Step 2: The seeds should be planted in the spring so that they have the whole growing season to establish themselves before winter. However pine seeds need to go through a process called stratification before they can germinate. This means that the seeds need to be exposed to cold temperatures such as the frost of winter in order to be stimulated into germination (3). You can either do this by planting them outside earlier in like December or January which should expose them to the proper temperatures depending on where you live. Or you can artificially recreate the stratification by exposing the seeds to cold temperatures in a controlled environment for a period of 1-3 months. Apparently if the seeds are soaked in cold water for 6-12 hours before they are placed under cold temperatures this may lessen the time it takes for stratification. Usually if you are purchasing the seed online this process has already been done(4)

Potted Mugo Pine
http://www.wabisabigardens.com/sculptedpine.html

·         Step 3: Pot the seeds in whatever you want to use. Fill the containers with a well-drained media of your choice. Placing more than one seed in a container is wise since not all of the seeds are going to germinate. They should be placed just below the surface, not too deep, and then completely covered by the media. (3)

·         Step 4: Water the media often but don’t soak the seeds completely, just keep it moist. The key to this process is patience because the Mugo Pine is a slow growing plant it may takes a month or so to see any changes with the seeds. Another method is to germinate the seeds by covering them with a wet paper towel and keep it constantly moist. This way you can see when the seeds germinate and plant them in the media as soon as they do. (3)

·         Step 5: Keep watering the plants. As soon as the empty seed coat falls off of the leaves the plant will be able to be planted outside. Each one should be put in about a gallon sized container so that it has room to grow. Keep up with the watering and if you take good care of the tree, it may be able to grow close to a foot in length by the end of the first year. (3)

Other Methods of Propagation:

            The only other method used to propagate the Mugo Pine is by taking cuttings. However the success rate is very low, it is not a very popular way to propagate the plant. To propagate the plant by cutting, you would take a cut from an already grow Mugo Pine. Make sure the cut is juvenile tissue, and then plant the cutting in a pot. Keep the media moist until it can grow roots which will take a long time since the plant grows very slowly. Rooting hormone is typically used to help cutting produce roots. The cutting is dipped into the hormone which can be a powder or a liquid before it is planted in the media to grow roots. Oregon State University did trials with cuttings of the Mugo Pine. In these trials they tested the effects of different rooting hormones. Usually rooting hormone aids in the process of a cutting growing roots. However in this case it helped certain cuttings root, but was very obviously harmful to the rooting of other cuttings. So depending upon the plant variety you are taking cuttings from it may be a gamble to use rooting hormone before planting the cutting. (5)

Works Cited:

(1)   – "Iseli Nursery." Iseli Nursery. N.p., 2000. Web. 14 Apr. 2013. <http://www.iselinursery.com/index.php?option=com_content>.

(2)    - "Seed." Wikipedia. Wikimedia Foundation, 04 Feb. 2013. Web. 14 Apr. 2013. <http://en.wikipedia.org/wiki/Seed>.

(3)    - "Grow a Pine Tree from Seed." Grow a Pine Tree from Seed. DesertMud, 2004. Web. 14 Apr. 2013. <http://www.desertmud.com/articles_details/ArticleID/1>.

(4)    - "Stratification (botany)." Wikipedia. Wikimedia Foundation, 29 Mar. 2013. Web. 14 Apr. 2013. <http://en.wikipedia.org/wiki/Stratification_(botany)>.

(5)    - Roberts, A. N., and F. W. Moeller. "Propagation of Mugo Pine Successful." Oregon Ornamental and Nursery Digest 12.1 (n.d.): 1-2. Print.