The Complete Guide to Seed Starting

May 21, 2020 7 min read 0 Comments

Seed starting in cell trays

Growing Your Own Food - A Beginners Guide

New to gardening this season? Looking to improve the local food system in your community?

We've got you covered. 

We have compiled some of the most common questions to create a "how-to" guide for seed starting along with other gardening tips. From choosing your soil mix to transplanting outdoors, rearing your own plants is one of the most rewarding things a person can do. These basic tips will have you off to a great start and hopefully on your way to planting a successful garden.  

Before we get into how to start seeds, you should know what you want to ultimately do with them! Where will you be planting them?  Before we get into seed starting, let's talk about creating an overall plan for your garden.

How Do You Create a Gardening Plan?

Creating a gardening plan can save you a ton of time in the long run.  Getting the area plotted out on paper can help you plan in a way that is easiest to manage and harvest. 

Make sure that you locate spacing requirements for the plants that you are growing.  Along with spacing, it is also a good time to consider planting your taller crops in the northern area of your plot and plant smaller plants closer to the southern area of your gardening plot. This will help to prevent shading that could be detrimental to your crops.

Certain plants can also be planted together to improve their success. A good example of this is with corn, beans and squash.  Planting these three crops together, "The Three Sisters", is a great example of companion planting.  Squash typically fills in the area for ground cover and helps to stabilize the corn plant. The corn acts a pole for the beans to climb, while the beans fix nitrogen into the soil to help the squash and corn thrive. 

Finding plants that grow well together this way is called companion planting.

Once you have your garden plotted out on paper, decide whether you will want to use raised beds or instead use garden rows. Raised beds take a bit of work, but improve drainage as well as accessibility to the plants.  Another option, if you are not interested in building a raised bed is to grow in large grow bags. This is also a great option for a rooftop garden, or in areas with inadequate soil.

When planning the row spacing, account for a three-foot pathway.  Leave enough room next to each of the rows for weeding and harvesting. Planting the rows too densely can prevent weed management, leading to smaller yields. When planting melons, cucumbers or squash the spacing should be increased in order to plan for sprawl or spacing for a trellis structure.


How Do You Choose Seeds for Planting?

Choosing which seeds to grow can seem overwhelming for the first time grower. It is important to consider a few things when picking out seed varieties. What types of vegetables do well in your area?

Locate your growing zone and use that as your guide when browsing seed companies to pick the best fit.  Next, consider what will sell in your area or if for a home garden, what vegetables do you and your family enjoy?

The last thing to consider is your skill level. If this is your first garden, focus on easier to grow crops to start. Some crops we recommend are: squash, lettuce, tomatoes, collard greens, bush beans, peppers, and melons.  Pick varieties that are labeled as disease-resistant when possible. Once you've picked your crops, get it on paper and start a garden plan.


When Should I Start Planting Seeds?

After mapping out your garden, find out when the last frost date is in your area and subtract 6-8 weeks from that date.  Knowing this date, you will be able to nail down the best timeframe to plant.  Planning this will ensure that the seedlings have enough time to develop before the transplant date. Now, that you have your timeframe for planting it is good to look into different ways to successfully propagate seedlings.  Seeds can be propagated in cell trays, soil block trays, or even just in small containers.  Many find the cell trays to be a very advantageous way to grow more starts in a smaller area. If you are interested in planting into cell trays, finding the right size is important.  Cell tray sizes vary in order to work with different crops and growth rates. Faster growing crops need cell trays that are able to hold more potting soil in order to provide for the growing seedling longer. 


What is the Best Soil Mix for Starting Seeds?

Choose a good potting quality potting soil with these key features:

1. Good drainage

2. PH between 5-6.5

3. Moisture rentention

4. Allows for airflow

These qualities are important, but it is equally important to use a clean, seedless mix when starting new plants.  Some key ingredients to look for in potting soil are: perlite, vermiculite, peat moss, coconut coir, compost, and a basic fertilizer or a ground limestone.  

(Check out:  Beginners Guide to Soil, Media, Amendments, and Fertility)

How to Plant into Cell Trays

Fill your cell trays halfway full with potting soil.  Take another cell tray and stack it on top of the cell tray that you are planting into.  This will pack down the dirt and create little divots to sow seeds into.  Plant 2-3 seeds per cell and cover the entire tray with the other half of the potting soil.  Water your newly planted seeds liberally.  You will then cover with a humidity dome and place on your shelf or on a heat mat if using one.  The humidity dome will maintain the perfect conditions for your seeds to germinate. Be sure to label your seedlings!


Germinating Seeds with a Humidity Dome

Once you have planted your seeds into your cell trays, it is wise to cover them with a humidity dome to maintain the best conditions for your seed during germination.  There is some debate on how to use humidity domes, but we believe when used properly, they increase germination success. 

Keep the humidity dome on the newly seeded tray until the first sign of germination.  After that remove the dome and set the tray under lights.  It is important to not leave the humidity dome on past the first sign of germination, as mold can occur.  Once under the lights, seedlings will need airflow and water.

Do I Need a Grow Light for Seedlings?

Setting up an ideal growing area for seedlings does not need to be expensive. Direct lighting for your growing seedlings is recommended for 14-16 hours a day.  This can done with a simple led light hung around 6 inches above the seed tray. A baker's rack works very well for this.

The three most important things that a seedling needs are proper air flow, adequate light, and a consistent temperature range between 68 degrees F and 80 degrees F.  All of these conditions can be obtained with the proper equipment. Many start their seedlings in a garage or basement.  These conditions can be created with the use of heat mats, led lighting, and air circulating fans.

How Often Should You Water Seedlings?

Seedlings should be watered daily. We believe the best method of watering seedlings is to bottom water them using 1020 trays. This method allows for the soil to wick the water from the bottom.  Bottom-watering is not only time saving, but it prevents any damage from happening to the newly emerged seedlings. If you prefer to top water, find a fine mist spray bottle and check your seedlings twice a day to prevent dry out. 

(Check out: Easiest Way to Water Your Seedlings)

When to Transplant Seedlings from a Cell Tray?

Typically your seeds will stay in their cell trays for 6-8 weeks.  After this time period, you will either need to transplant into larger pots or transplant the new seedlings outside. Check your seed instructions and pay attention to your frost dates before transplanting outside.  A developed root system needs to be in place before a successful transplant can happen. Another thing to look for is the development of the "true" leaves. 

(Check out: When to Transplant Your Seedlings)

Hardening off Seedlings

Before transplanting your seedlings, it is important to expose your seedlings to cooler air. This is called hardening off. Hardening off your transplants will help to prevent shock.  Expose your baby plants to cool nights for about a week before planting. For more information on this check out: Transplanting Essentials.

Transplanting Seedlings Outdoors

After hardening off your seedlings,  it is time to plant.  Water your seedlings before and after planting. Some use special tools to remove plugs from cell trays, you will find what works best for you.  Start planting directly into your garden space, paying special attention to air pockets in the soil. If you are using landscape fabric, you will want to install that beforehand.  Plant the plug into the soil until the plug shape is not visible, leaving no gaps. Water in the transplant and continue to water often as the roots start to establish. Always plant during cooler times of the day.  It is best to plant in the morning to prevent sun damage to the root systems.  After transplanting, it may be a good idea to cover the rows while your seedlings are at their most vulnerable stage. 

(Check out: Quick Guide to Ground Covers on the Farm)

Protecting Seedlings

Those newly planted seedlings need to be protected from wind, insects, and birds. Insect netting is a great tool for this.  Not only does insect netting create a barrier around the plants, but it also cuts down on diseases caused by insect infestations. 

Shade cloth or netting is another option to consider when looking for protection for your new transplants.  Shade cloth not only protects your plants from sunburn, but it helps them to better utilize UV rays.  The reflective coating of the shade cloth helps to diffuse the light into a more usable form for plants, improving their growth and health overall. 

Beneficial insects are also a good way to protect your seedlings.  The use of beneficial bugs helps to keep pest numbers at a more manageable place without risking pollinators with the use of chemicals. (Read more: The Importance of Beneficial Insects)





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