1. Propagation in Plants
Horticulture I
Unit 4.02

2. Two Types of Propagation
Sexual
Asexual

3. plant propagation vocab
Corm – an enlarged, bulb-like, fleshy structure found at the base of a stem
Rhizome – a creeping underground stem, usually horizontal, that produces roots and leaves at the nodes (ex – cannas and bearded iris)
Stolon – a creeping above ground stem that grows horizontally and produces roots and shoots at the nodes (ex – strawberry)
Tuber – a swollen, modified stem that grows underground (ex – potato)
Sucker – a shoot or stem that originates from the roots

4. Sexual Propagation
Starting plants from seeds

5. Germination Rate
The percentage of seeds that sprout (75 out of 100 = 75%)
Can be affected by temperature and moisture
Can vary depending on type of plant and quality (viability) of the seed

6. Seed Viability The seed’s capability of growing or developing
Affected by temperature and moisture
Embryo
Seed Coat
Endosperm

7. Planting Seeds How deep to plant seeds depends on size of seeds
Plant seeds no more than 1 ½ times the diameter of the seed
Larger seeds are planted deeper
Smaller seeds are planted shallow (ex – petunia seeds are tiny)
Water small seeds from bottom by soaking to prevent burying them

8. Seedlings (small plants)
The first set of leaves are called cotyledons
Monocots produce one seed leaf
Dicots produce two seed leaves

9. Seedlings (small plants)
True leaves are the second set of leaves
Transplant seedlings when the first true leaves appear
Before planting in the outdoor environment, reduce humidity and water and make the environment more like the outside to “harden off” plants

10. Advantages of sexual reproduction
It is the fast way to get many plants
It is easy to do
It is economical

11. Disadvantages of sexual reproduction
Some plants, especially hybrids, do not reproduce true to parents
Some plants are difficult to propagate from seeds

12. Plants started by seed Marigold Impatiens Begonia Coleus Salvia
Shasta daisy
Pansy

13. Asexual propagation Starting plants by means other than seed Cuttings
Layering
Division
Separation
Grafting
Budding
Tissue culture

14. Cuttings
Stem
Leaf
Root

15. Stem Cuttings Start with sterile flats, soil, and tools
Must include a node
Node is the point along a plant stem where leaves or other stems are attached
Internode is the area between two nodes

16. Stem cuttings
Cutting is taking a 4-6 inch piece of the plant and forcing roots to grow
Using hormones and dipping the cutting in fungicides help speed up rooting
Rooting media should be about four inches deep

17. Stem cuttings https://www.youtube.com/watch?v=71dYCsVAL8k
Herbaceous plants are soft tissue plants
Geranium, impatiens, begonia, coleus
Woody plants are plants that produce woody tissue
Holly, abelia, rosemary

18. Gather all materials needed
Stem Cuttings-Step 1
Gather all materials needed

19. Cut 3 to 4 inch shoot from stem tip
Stem Cuttings-Step 2
Cut 3 to 4 inch shoot from stem tip

20. Remove lower leaves from the shoot
Stem Cuttings-Step 3
Remove lower leaves from the shoot

21. Dip cut surface in rooting hormone
Stem Cuttings-Step 4
Dip cut surface in rooting hormone

22. Thoroughly moisten rooting medium
Stem Cuttings-Step 5
Thoroughly moisten rooting medium

23. Stick one or more cuttings in rooting media
Stem Cuttings-Step 6
Stick one or more cuttings in rooting media

24. Stem Cuttings-Step 7
Cover with plastic wrap or place on a mist bench in a warm area away from direct sunlight.

25. Once rooted, cuttings can be separated carefully and transplanted
Stem Cuttings-Step 8
Once rooted, cuttings can be separated carefully and transplanted

26. Leaf cuttings https://www.youtube.com/watch?v=lVaZI1Nrgxo
Usually propagated from herbaceous plants
Midrib vein must be cut in order to make roots form
Plants that can start from leaf cuttings:
African violet, philodendron, snake plant, jade plant

27. Root cuttings https://www.youtube.com/watch?v=POfTI4oWObo
Should be spaced three inches apart in rooting area
A sand, vermiculite or perlite mixture is a good media for root cuttings
The best time of day to take a stem, lead, or root cutting is early morning because the plants have more moisture
Plants that can be started by root cuttings:
Hosta and daylily

28. Layering
Air layering
Trench layering
Mound layering

29. Air layering Make an incision at the node of a branch
Dust with rooting hormone, place sphagnum moss in plastic and wrap around the incision forcing roots to grow on the stem
Once roots form, remove below the new roots for a new plant
Ex) decora rubber plant and weeping fig

30. Trench layering Cutting a trench and laying a branch in the trench
Types of trench layering are simple, tip, and serpentine
Ex) grapes and clematis

31. Mound layering
Mounding the soil on a branch
Ex) azalea

32. Division
Cutting apart rhizomes, tubers, runners, stolons, or suckers to get new plants
Used on plants that grow in clumps
Ex) hostas, daylilies, irises, some grasses

33. separation
Separating natural structures of a plant without making a cut
Ex) bulbs and corms

34. grafting
Joining separate plant parts together so that they form a union and grow together to make one plant
Tools needed – knife, tape, wax
Plants must be related to each other and normally in the same genus or family
Scion is the piece of plant at the top of graft
Rootstock is the piece of the plant at the root or bottom of the graft
Ex) maples, fruit trees, sweetgum, pecan

35. budding A form of grafting when a bud is used instead of a scion
Methods of budding
Patch budding
T-budding
Chip budding
Ex) rose
Step 2
Step 4
Step 1
Step 3

36. budding
Successful budding requires that the scion (top) material have fully-formed, mature, dormant buds and that the rootstock be in a condition of active growth such that the “bark is slipping” which means that the vascular cambium is actively growing, and the bark can be peeled easily from the stock piece with little damage

37. Tissue culture Also known as micropropagation
A sterile environment is necessary for micropropagation (biotechnology)
It is a good way to get the most plants in a short period of time
It will give you a plant identical to the parent plant
Ex) impatiens, flower and vegetable plants

38. Advantages of Asexual Reproduction
Plants mature in a shorter time
Budding is faster than grafting
In trench layering, plant forms at each node on covered stems
Some plants do not produce viable seeds
New plants are same as parent plant

39. Disadvantages of asexual reproduction
Some require special equipment and skills, such as grafting
Cuttings detach plant parts from water and nutrient source
Some plants are patented making propagation illegal