Starting seedlings indoors without a greenhouse

Starting seeds indoors is not only an enjoyable and rewarding activity, there are many benefits that can bring you more success to your gardening endeavors. 
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1. Variety - Starting seeds indoors allows you to choose the seed variety and source, giving you more ownership over your garden.
2. Timing - Timing is everything when planting a garden, and starting seeds yourself gives you the freedom to control when your plants will be ready.
3. Quality - You control the quality of your plants based on the type of nutrients, light, and care that you provide them. 

If you don't have the luxury of owning a heated greenhouse, or a very warm and sunny room, there are steps you can take to grow plants in almost any room, shop, or garage.  In this blog post we will explore all of the aspects involved in successfully starting your seedlings indoors so you can get a jump on the season and choose plant varieties that interest you. 

Selecting Seeds

The first step to starting seedlings indoors is obtaining high quality seeds. Browsing seed catalogs and selecting interesting varieties to try is one of the most enjoyable parts of this whole process.  The trick is to select companies that produce high quality seed and varieties that will perform well in your climate.  Here in NW Oregon we have short but hot summers bookended by cold and wet spring and fall seasons. Picking out your own seeds allows you to plan and time your plantings based on the seasonal conditions of your area. We recommend several great seed companies in our blog: "Choosing the best seed companies for Oregon and PNW gardens"

What do plants need to grow?

At a very basic level, there are three key inputs your plants need to grow - water, nutrients, and light.  Keep in mind that these are the bare minimum requirements that plants need to grow, but we don't want our plants to just grow - we want our plants to thrive!  We will also discuss the importance of air circulation, soil, temperature, and acclimation. 

Water

Seeds need adequate moisture for germination, but once germination occurs you will want to limit your watering to only when the plants absolutely need it.  Over-watering is one of the most common mistakes people make when taking care of new seedlings.  Over-watering can lead to fungal and bacterial disease that can kill young seedlings before they even have a chance to grow.  To germinate your seeds use a spray bottle to mist the soil to keep it adequately moist, or use a mist setting on a hose nozzle if you are starting your seedlings in a place where you can water with a hose.  You can also use a germination dome to help keep moisture in until the seedlings have sprouted:

50 cell humidity dome kit at Bootstrap Farmer

Light

Plants under LED Grow Lights

Good quality light is one of the most important pieces of the puzzle when starting your plants indoors.  Not all lights are created equal and not all of them emit the quality and intensity needed for strong healthy growth.  A sunny window will definitely grow plants, but chances are there is not enough sun coming through for a long enough period of time to avoid seedlings that stretch and become leggy - this is where supplemental lighting comes in.  Lighting technology has come a long way, and whether you are an advocate for legalized marijuana or not the fact is that the marijuana industry is responsible for most of the advances in lighting technology.   Using grow lights in the past meant hanging big bulky lights and ballasts that would produce a dangerous amount of heat, which required proper ventilation.  Today we have very safe, effective, and affordable lighting in the form of LED grow lights.   LED lights are quiet, they produce very minimal heat, and they use less energy than the traditional grow lights of the past.  We use the following lights and highly recommend them:

Sunraise 200watt Dimmable LED Grow Light

Spider Farmer Dimmable Full Spectrum LED Light

Nutrients

Nutrients are the essential building blocks to strong healthy growth.  Just as we need a balanced diet to maintain health and growth, plants also need the same.  There are countless brands of fertilizer out there, which can make the process of selecting the right one for your needs a little daunting.  For starting seedlings you will want to choose a liquid fertilizer so you can water your seedlings with a nutrient solution in a watering can.  For an in-depth discussion about choosing the right nutrients for your plants please read our dedicated blog post here: How to choose the best organic fertilizer for your garden

Air Circulation

Often overlooked, air circulation is incredibly important for strong plant growth and disease prevention.  Plants that are grown indoors are not subject to the harsher conditions outdoors, including winds.  Plants develop an overall stronger structure in response to wind to prevent breakage.  You can think of it as building a strong musculoskeletal system.  If plants are not subjected to these conditions they will grow weaker structures and be more prone to breaking when you put them outside into the garden.  A constant steady breeze on your plants, created by a table top or box fan, will mimic the natural processes and will result in healthier plants.  Another reason air circulation is important is to prevent fungal and bacterial diseases.  Fungus and bacteria both thrive in warm and moist environments, so giving your plants good airflow will help mitigate some of these issues.  

Soil

Soil is not just an important consideration in the garden, it is also essential to have a good healthy soil to start your seedlings with as well.  Most seedling mixes include a combination of peat moss, aged forest products, perlite, and a nutrient blend (depending on the brand of soil).  We do not recommend using a brand like Miracle Grow for your seedling soil.  Plants are much more resilient if they are grown in a natural soil mix that includes additives like bat guano, mycorrhizal fungi, and beneficial bacteria.  We highly recommend Fox Farm brand soils to produce healthy plants. They have two great products to choose from for starting seedlings - Happy Frog Potting Soil and Ocean Forest Potting Soil.   If you live locally you can find FoxFarm products in garden centers including Linnton Feed.  If you don't have a FoxFarm retailer nearby you can find the soil online:

FoxFarm Ocean Forest Potting Soil

FoxFarm Happy Frog Potting Soil

Temperature

It is important to understand the germination temperature of your seeds in order to have success. Most vegetable seeds undergo germination between the temperatures of 70 to 80 degrees. Flower seeds can sometimes have very specific temperature requirements, which will usually be provided to you on the seed packet or on the website of your seed source. If you are growing plants in an unheated shop or garage, the germination temperature can be achieved by using a seedling heat mat. Heat mats warm the soil from below your seed tray and provide your seeds with the optimal temperature for growth. We recommend the following seedling heat mat for germination purposes:

Electra-grow Heat Mat with Frame

Acclimation

One of the most important steps in the process of starting your own seedlings is the final step - acclimation. Acclimation is the process of allowing your transplants to adjust to outdoor conditions slowly to avoid damage from sun exposure and temperature. Even if your plants are grown under bright LED lights, they will still need to be slowly acclimated to the harsh UV rays of the sun. You can achieve this by gradually introducing your seedlings to sunlight over time. When you are ready to bring your plants outdoors, it is important to give them indirect sunlight at first. This can be achieved by putting them in an area that gets dappled sunlight, like under a large tree. If you are growing seedlings on a large scale you can also purchase a shade cloth to provide partial shade to your seedlings as they adjust to being outside. We recommend using a 50% shade cloth for hardening off seedlings:

50% Shade Cloth at Bootstrap Farmer

Another aspect of acclimation is temperature adjustment, which can be acheived by hardening off your seedlings. If your plants have been growing at a perfect 70 degrees under zero adverse conditions, they're going to be very lush and susceptible to damage. Hardening them off in the partial shade where they are receiving normal temperature swings will strengthen the plants and get them ready for their final spot in the garden. 

For best results, harden off your seedlings in partial shade for at least a week before planting them in the garden.

Conclusion

Now that you have a basic understanding of what is needed to start plants indoors we hope you find some interesting seeds and give it a shot! This blog post covers the absolute basics, so please feel free to contact us if you have more in-depth questions - we would be happy to help!

We understand that starting seeds indoors is not something that everyone has the time or resources to do. If you live locally we have plants available for purchase in St. Helens, Oregon, at the Real Deahl Gift Store during the season. We hope you stop by and see what interesting plants we have to offer. 

Happy growing!

Corey & Susie