By starting seeds indoors you are able to extend your growing season by getting a head start. Once the weather is free from a frost threat you can transplant them outdoors and have an established garden. Starting seeds indoors can be a daunting task especially for a novice, but we intend to shed some light on the topic. Pun intended.
When to start your seeds is determined by when you can safely transplant them outside. If you are located in the Midwest, you may refer to
Hummert’s Midwest Vegetable Planting Guide
for optimal planting time outside, otherwise your local county extension agent or the internet can help you determine the best time. These charts will give you recommended time to start your seeds and often time from sowing to harvest.
The first thing to do when starting seed is to make sure you have viable seed. A viable seed is capable of germinating and producing a new plant. There are many factors that could affect the viability of seeds such as where and how they were stored or the type of seed. If you have seed that is held over from last year, or longer, it is a good idea to test its viability. There are several ways to test viability of seed, but the most common way requires only regular household items. All you need is the seed in question, a plastic sandwich bag, and a paper towel. The first step is to place 10 seeds on top of the paper towel. Next fold the paper towel in half to cover the seeds and place the paper towel in the plastic bag. Lastly, moisten the paper towel, seal the plastic bag and place in a warm location. Write the date that you began the test on the bag. Within a week most of the seeds inside the dampened paper towel should start to sprout if the seeds are still viable.
10 sprouted seeds = 100% Perfect
9 sprouted seeds = 90% Excellent
8 sprouted seeds = 80% Good
6-7 sprouted seeds = 60-70% Fair
5 sprouted seeds = 50% Poor
Seeds that fall into the 60-70% germination rate will have to be sown heavier than the normal rate. Some gardeners would recommend not bothering to plant seeds that germinate at 50% or lower rates, but many gardeners instead of discarding these seeds would rather sow them at the heavier rate or direct sow them into the garden and not become too optimistic about the results. No need to waste!
There are many container and media options to choose from when starting your seeds. Containers for starting seeds should be clean and sturdy and should fit into the space available for growing plants in the home. Having the proper container helps get seedlings off to a good start and may save work in later stages of seed development. Plastic, clay, peat pellets, or peat pots are all happy homes for your viable seed. Just be sure that they are sterile to avoid damping off or any other plant diseases, free from harmful chemicals, and drain well. The next step is choosing a growing media. Commercial seed starting mixes have been perfected for your success, so they are always a good choice, but mixing your own by using materials such as fine-medium vermiculite or milled sphagnum moss is also a good option. Just note that your medium should be loose, well-drained and of fine texture. Experiment with different combinations of pots and media to determine what works best for you. The key is to make sure that your medium is evenly moist when you beginning to plant your seeds.
Finally all the decisions have been made and it is actually time to plant your seeds. Fill your containers with the moistened media to about ¾” from the top of the container of choice. Lightly level and press the media in the container, but avoid pressing too hard. Pressing the media too much will reduce aeration and result in poor root development. Sow the seeds uniformly and thinly either by hand or by using a small hand seeder. Cover the seeds if required. Lettuce and carrots are positively photoblastic, meaning they are stimulated by light and require light to germinate. Tomatoes, however, are negatively photoblastic, meaning they need darkness to germinate. For seeds that require more light for germination, they should be planted closer to the surface and possibly left uncovered. As a general rule, seeds other than very fine seeds should be covered with soil to a depth of about two times their diameter. Label you plants accordingly with the plant type, variety, and date of planting. Moisten the surface with a fine mist and place a propagation dome over the top of the propagation tray or containers to help retain moisture and humidity. The plants should not need to be watered until they have germinated.
It is amazing how often we hear people say that you can grow seedlings in a sunny window. They must live somewhere near the equator and have a sunroom. Seedlings are happiest with 14-16 hours of bright light. Seedlings actually require more light than mature plants. Fluorescent fixtures with two 40 watt bulbs or a small propagation table is an inexpensive way to achieve this. Not only is the amount of light important, but also the placement of the light. It is recommended to keep the seedlings within four inches from the bulbs. This will require you to continually adjust the height as the seedlings grow. It is crucial that your tiny plants also get some down time. We recommend connecting your grow lights to a timer to let them rest and you won’t have to remember.
About two weeks before your seedlings are scheduled to be transplanted into the garden, you should begin “hardening” them off. Hardening off is a term used to describe the gradual acclimation to the harsh outdoors to reduce or prevent transplant shock. Begin by reducing temperatures, watering less frequently, and fertilizer less often to help toughen them up for the outdoors. If you do not have a cold frame to help with the hardening off process, you will need to move the plants in and out of the house. Place tender plants outdoors, providing protection from full sunlight, strong wind and temperatures below 45 degrees. Start with a few hours outside and gradually increase the time placed outdoors everyday. Try to ease them out into the real world towards the end of the second week. The best day to transplant permanently into the garden is on an overcast day when the wind is mild.
Before long, you will have lush, bountiful garden that all of your friends and family will be jealous of. They will credit you with a true green thumb! When the time comes to start seeds indoors next year, the task won’t look so daunting. You will be a seasoned expert!