Sexual Propagation

Why Use Seeds for Propagation? Reliable Uniform Crops Low Cost Easy to Handle Mechanical Plantings Shipping (Seed vs. Plants) Storage (Cool, Low Humidity)

Plantings Most of our food and fiber crops are planted directly in the field. The soil of the seedbed should be moist. Should be of smooth, fine, crumbly soil, and free of clods.

What conditions are necessary for seed germination? Seeds are designed to wait for favorable conditions to begin growth. They may lay dormant for many years before conditions allow them to begin to grow.

Stratification When the seed must go through a period of cold temperatures before it will germinate.

Scarification Breaking down of the seed coat. Some seeds have such a hard, thick seed coat that they prevent the absorption of water to enable germination to occur. You can use sand paper or files to damage the seed coat.

Planting Depth Rule of Thumb – Plant seed twice as deep as the seed is. Really small seed should be planted in greenhouses and then transplanted to field.

Irrigation in Field Flood Field and allow plants to be watered by capillary action. Sprinklers What would be a problem? Be careful to avoid crusting of the soil. Why?

Planting in Flats Usually done in greenhouses. Controlled conditions – Quick Medium that holds moisture and drains easy. Sand, perlite and peat moss Plant in rows or sporadic. Too many seeds in flat = Spindly

Planting in Flats Continued Once you put seeds in tamp them down. Cover with a thin layer of soil on top Helps with moisture Fungus Work with clean sterile tools and environment Water Occasionally Careful not to wash out Best Temperature 70-80°F

Germination process The germination process begins with the absorption of water. The seed swells and the embryo changes from a dormant state to an actively growing plant. The embryo draws energy from starches stored in the endosperm or cotyledons. The embryo’s root emerges from the seed and develops into the primary root. Then, the stem of the embryo sprouts upward.

Problems that Can Occur Old seed looses viability, percent reduced. Even Moisture at all times Temperature to Low or High (Field) To shallow planted (Dry) To deep planted (Energy)

Post Germination Care Constant Supply of Water Low Fertilization Bright Light reduces spindly Maintain temperature

Transplanting Seedlings can generally be transplanted after their first true leaves develop fully. If going direct to field, more time to mature. Hardening Reduce water, day/night temperatures. Handle only by leaves (not roots or stem) Depth Dispose of damaged or diseased plants

Transplanting Double water plants right after transplanting. Water immediately Make hole larger than the root ball

Precautions for Young Plants Sunburn Over watering Extreme Temperatures Pests / Diseases