For indoor seeding proceed as follows
Provide suitable seeding boxes, or flats, about 3 inches thick. Use hotbed or cold frames if available and if large quantities of plants are to be grown. Fill with fine loamy soil that does not cake readily. Press the soil down firmly and evenly with a small piece of board. When firm, the surface of the ground should be about 3/4 inch below the top of the box.
Make shallow, narrow trenches about 1/4 inch deep crosswise of the box. Scatter seeds in trenches. Cover or sift with fine soil and compact firmly. The depth of covering will vary with the size of seeds. Sprinkle carefully to avoid washing, cover the box with a pane of glass and put where the temperature is high enough to start germination. Transplant young seedling when first true leaves have formed, into other boxes, beds, or pots to give more room for growth and produce better root and top development.
Set out young plants. Since indoor-grown plants should be “hardened,” before placing in permanent outdoor locations. Expose the plants to outdoor conditions for an hour or two during the warm part of the day. Gradually lengthen this exposure period over several days until they have been exposed the full 24 hours. Set out plants in late afternoon or evening. The best time is following a good rain when the soil is in working condition. Prepare holes for setting plants to a good depth, so the danger of drying out will be minimized.
Removed plants from bed or boxes by cutting around them with a knife, removing a block of soil with the plant roots intact. Place plants in holes and partially cover roots with soil. Press the soil lightly around plants. Pour in a cup of water. When it has soaked away, finish filling up around the plant. Space plants with plenty of room for proper development and shape. It usually promotes better flowering and greater ease in cultivating and caring for them.
You can read: Step in Growing Flowers
Set out bulbs and roots
After studying the planting suggestions and seasonal requirements of the plants being considered set them out in proper season. Methods and time of setting out and handling roots and bulbs vary widely with the different varieties and with the locality.
Cultivate and car for plants
Stir the soil after heavy rains to prevent caking. Do not work the ground when too wet. Keep gardens free of weeds. Water thoroughly at frequent intervals during dry weather. A light mulch of leaves or straw will help prevent excessive evaporation and drying of the soil. Follow practices recommended for digging and storing roots and bulbs that must be taken indoors during the winter. A procedure recommended is to dig them carefully during dry weather shortly after the first killing frost. Cut off tops, leaving 3 to 4 inches of stem attached to roots or tubers. Leave them off the ground to dry for a few hours.
Store in dry, cool place where the temperature will not drop below 40ºF, during the winter. Burn withered leaves and stems to prevent disease. Protect outdoor flower plants during the winter with a layer of straw manure, hay, leaves, or coarse ashes after the ground is frozen.