For the normally colder parts of central Suffolk County, after April 20th is used as the date for the average last spring freeze. For western Nassau County to New York City, use before April 10th as the date for the average last spring freeze. Instructions for certain tender vegetables and annual flowers may direct you to delay planting outdoors until all danger of frost has passed. It is very helpful to have a coldframe outdoors where such plants can be kept during the day and moved back indoors at night. There are many types of seed starting containers to choose from depending on your needs and preferences.
Containers can be simple and inexpensive or costly and elaborate.
You will need to judge the advantages and disadvantages of the many containers available and see which ones meet your needs at the lowest price. Many can be re-used season after season if they receive a little care. Be sure you scrub clean all previously used containers and sterilize them against insect, disease and weed pests with a suitable disinfectant. Overlook this sterilization procedure and your seedlings may end up succumbing to a pest, such as root and stem rots, and you will have very little recourse against it. Many gardeners start seeds in various plastic and cardboard containers which they would have otherwise discarded with their weekly recyclable products.