Indoor Starts vs. Direct Sown

Our thoughts are turning from enjoying those lazy winter weekends when gardening is just not happening to maybe summoning up the inspiration to start planning what we will do differently this year and what new plants we will try. There are seed catalogs and spring gardening magazines to tempt us.

Memories of last year’s disappointments are fading and we’re ready to get our fingernails dirty again. All the different varieties of plants available when we plant from seed are irresistibly tempting. We start to wonder if we dare try a little indoor propagating or if we should wait a little longer and sow our seeds in beds outside.

Indoor Seed Starting

There’s much to be said for the idea of starting some seeds inside. When we do, we have control over the conditions of germination and growth. We can provide a growing medium that has a uniform, fine texture and is well aerated and loose. We can assure even watering by never over watering or letting the planting medium dry out. We can artificially control the temperature and light conditions that our seeds/ seedlings are exposed to, guaranteeing optimum conditions not possible with direct sowing. We can take steps to reduce pests, weeds, and disease. Using

a soilless mix helps prevent the fungal disease known as damping- off that can kill seedlings. The mixes are free of weed seeds and insects. The most diligently prepared outdoor gardening beds cannot offer these advantages.

Jumpstart the Season

By sowing seeds inside, we can get a jump on the growing season. Plants started indoors can generally be started four to twelve weeks prior to transplanting outside. (See seed packet for specifics.) This allows plants to produce flowers or fruits or vegetables much sooner than seeds that are direct sowed. If we are interested in varieties that require a long growing season, getting this head start may make all the difference. We are not at the mercy of the weather outdoors.

Save $$$

It’s possible to save money over paying for plants at the nursery. Any price comparison trip will show that a package of seeds is much more economical than gallon sized plants or even six packs. Also, the plant varieties that are available by buying seed packets at local retail outlets are much more extensive than what is available in living plants. If you factor in the varieties that are available in catalogs or at on-line sources, the options are clearly superior. To avoid disappointment, make sure you are purchasing quality seed.

Some Considerations

There can be a downside, though, to planting indoors. Start up costs can be significant. Depending on the quantity of plants you are hoping to grow and the space you have available to you, you will want to make sure you can provide the environment necessary for the seeds to germinate and thrive indoors until you are ready to transplant outside. At a minimum, you will need seed germination media, containers, seeds, fertilizer, and adequate lighting and temperature.

Timing is critical. In winter we may be tempted to plant seeds too soon. If we keep seedlings indoors for too long a time they may not perform well when transplanted outside. If we plant outdoors too soon, our pampered plants may be doomed by a late frost or other inclement weather. We also must remember to allow time for an acclimation period in which the seedlings are “hardened off” before planting. A shaded cold frame can be used as a transition space. Ideally, transplanting should occur on a cloudy day when the new plants will not be challenged by hot, direct sun.

Lots of vigilance will be required. Watering must be done diligently. Both over watering and under watering can spell disaster. Bottom watering is a good idea if the container only sits in water long enough for the soil to become moist. Excess water can result in oxygen depletion of the soil. Fertilization is also required for seedlings grown in an artificial growing medium. A soluble fertilizer is best and should be applied at half strength initially. This should be followed up every two weeks at regular strength to provide optimum results.

There may be space limitations to consider. Outside, we are only limited by the amount of ground we have to plant in. Indoors, we must either give up counter space or provide special shelving systems to house our fledgling seedlings.

Direct Seeding

Sometimes there are advantages to sowing our seeds outside. It takes less work to direct sow. Preparing the soil for seed may need to be more precise than with already thriving plants, but either way, adequate soil preparation is always required. Of course, in spring wait until the soil is not overly wet and the soil temperature has warmed adequately. As the seeds sprout, thinning of seedlings may be required, but not transplanting. Do make sure to protect from pests and competition from weeds. Direct sown plants may be healthier than seedlings that we’ve been forced to hold off too long to plant due to poor outdoor weather. Seedlings generally stop growing temporarily when transplanted and sometimes suffer transplant shock. Some plants just don’t generally transplant well. 

Examples include zinnias, melons, squash, carrots, and potatoes. Check the seed package to be sure. Plants that are sown in place don’t face these challenges. So, just like everything else in gardening, the answer to whether to start indoors or direct sow later is—it all depends! We all discover what works best in our own gardens and some of it just comes down to personal preference.

hichever way you decide to go, make sure to enjoy!

References

OSU Master Gardener Training Manual. http://hcs.osu.edu/mg/manual/prop.html

California Master Gardener Handbook