Germinate Seeds Inside Or Outside?

Wild Lettuce

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Whether the seeds you are starting are going to be growing outdoors once they have germinated – or if they are going to be additions to your indoor garden, seed starting inside is often the best way to ensure success.

Germinating Your Seeds Indoors Protects Them

The tiny seeds and seedlings do not do well with harsh weather changes and a late frost or excessive rain can prevent them from growing. There is also the problem of birds, rodents and other little pests getting into the seeds as a food source.

There are many commercial helpers you can buy to make germinating seeds an easy project. Peat pellets that come with a miniature hot house require nothing more than adding water to the seed and peat and covering with the supplied lid. But some water, high-quality soil, sunlight and time are all that you need.


Germinating seeds


Preparing For Germinating Seeds

Like plants, seeds like to be kept moist so a good drainage system in the pot is necessary so they do not get too much water. There is no solution to them getting too dry though, just don’t forget to water them.

Your planting containers should be at least three inches deep, with small holes for drainage. You can use plastic yogurt or cottage cheese containers, 3 or 4 inch plastic plant pots or half-gallon milk cartons cut lengthwise, all with drainage holes punched in the bottoms. I don’t recommend reusing egg cartons or old nursery  packs as they don’t hold enough soil volume and dry out too easily.

My favorite seed raising container is …

… the inner cardboard tube from a toilet paper roll! It is a perfect size, and if there are a number of them, they don’t dry out too quickly. And, the best thing about them (apart from the fact that they are free) is that when your seedlings are ready to be transplanted – you don’t have to disturb them at all.

As the cardboard decomposes quickly once in the ground, you can just plop the whole thing directly into the hole in the garden. There is next to no transplant shock as the roots are not disturbed at all – perfect!

Below, you can see some nasturtium cuttings in their toilet roll planters. I have them in a plastic container so I can see when the roots appear at the very bottom of the roll, and I need to plant them out. Being extremely frugal, I cut the rolls in half for this type of cutting. This is only because they don’t need to be so deep and I save a little bit of my seed raising mix, too.


Planters Made From Toilet Rolls


What To Use For Planting Soil

Buy and use a good quality seed starting mix, available from any good nursery or garden center. (Ordinary garden soil is not a good choice, as it often contains weed seeds and fungus organisms and it compacts far too easily.) Seed starting mixes are sterile and blended to be light and porous so your fragile seedlings get both the moisture and oxygen they need to thrive.

In a big bucket, add water slowly to the seed starting mix and combine well. You want it to be thoroughly moistened but not soggy – about the consistency of a wrung-out sponge throughout before you fill your containers. Fill each container to an inch below the top and tap it on the tabletop to settle the mix. Use a plastic or wooden marker with the variety name and sowing date and slide it into the container.

With the side of a pencil or chopstick, make a seed furrow about 1/4 inch deep and carefully drop in individual seeds about an inch apart. Sift some more starting mix between your hands to fill the furrows and firm gently to be sure the seeds have good contact. Use a spray bottle to water the seeds in with a fine mist. via Renees Garden


Cucumber Seedlings Growing


Other Important Considerations For Germinating

Germinating seeds is relatively easy, BUT there are a few crucial elements you need to be aware of …

Soil Temperature

Most seeds require a warm soil temperature to initiate germination. Generally, seeds germinate best at a soil temperature of 64-72 F (18-22 C). Keeping the temperature within this range can be hard, especially for seeds which take several days or even weeks to germinate.

Air temperature is generally warmer that the soil temperature, and is not sufficient enough to warm the soil. Bottom heat from specially designed mats or cables are ideal but you can also place your containers on top of the fridge, or radiator, etc.

Soil Moisture

When sowing seeds inside, soil moisture is equally as important as temperature. Seeds need water to help soften the seed coat and stimulate the root development. If your soil is allowed to dry, the germination will be delayed or, in most cases, ended.

To keep the soil moist, mix the growing medium with water, enough so that if a handful is squeezed, a small amount of water will run out.

After mixing, sow your seeds according to directions and then cover the containers with clear plastic. We really like those “mini-greenhouse” units that come with clear domes and holding trays. You can also use sealed bags or plastic wrap to keep your medium from drying out.

If your medium begins to dry out too fast, use a water bottle which will provide a fine mist or watering can with a gentle nozzle, as to not disturb the seeds. After germination, be sure to remove the plastic and place plants under grow lights or in another bright light location.


Lighting for your seedlings is extremely important. Without sufficient light, your young plants will become tall or “leggy”, which will make them weak and easy to break. Ideally, you should use a proper plant grow-light … or at the very least an adjustable fluorescent lights when growing plants indoors. Have your light suspended from the ceiling, or use a table top or shelf style of lighting stand to hang over the seedlings. Your lights and the plants must be only 3-4″ from the lights at all times for proper growth.

You should keep your lights on for about 16 hours a day – we recommend you use an automatic timer to turn on and off your lights. If you don’t have lights, you should grow in a bright south facing window. via



What Next?

Great … you have made it this far! Now, prepare for some disappointments, you shouldn’t count on all of the seeds sprouting even if you have purchased seeds from a reputable source some will be duds. For this reason, make sure you plant more of each seed than the desired number of plants you are looking for.

As the seedlings begin to sprout, continue to keep them moist and turn them regularly to create even sun exposure.

Transplanting Seedlings Outside

When the leaves start to come out you can begin the process of transplanting. Whether you are going to be growing the plants indoors or outdoors it is the same procedure. Gently take the new seedlings with the roots and plant it in a new pot. Or, if you are transplanting outside into your garden – then you can plant your new seedlings directly into the ground.


New Seedlings  In Garden Bed


Transplanting Tips For Success

Now that you have nice healthy seedlings it is time to transplant to your garden. The most common mistake by beginner gardeners is to rush this process.

Before planting your tending seedlings outside you must subject them to a “hardening off” period. Inside grown plants must be gradually exposed to outside conditions or they are likely to be stunted or die before they adapt to their”harsh” environment. The process of “hardening off” requires approximately two weeks but this can vary depending on the method you prefer to use.

A couple of weeks out from your planned transplant date you should reduce the amount of water the seedlings get. Let the soil become a bit dry-looking between watering. At least a week out from transplant time, start exposing the plants to outside conditions. You want that first exposure to be numbered in hours. Put them out in a shady, protected place for a few hours (say, mid-morning to early afternoon). If you live in cold climate you may want to have a shaded cold frame available.

After a couple of days of short exposure, you should be able to leave the seedlings out for the day, still in the shade. Each day, nudge them closer to a spot that gets full sun, or uncover more of the cold frame. Within a few days leave your seedlings fully exposed to the elements, day and night. Only then should you transplant to the garden. via

Want To Share?

Got some great seed starting tips of your own that you would like to share with our readers? You are welcome to leave your comments and advice in the comments section below …



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