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Wyoming growers may consider starting seeds indoors before planting outside

by Wyoming Livestock Roundup

“This is the time of year we start flipping through seed catalogues or wandering around the hardware store, dreaming about the beautiful gardens we will have this year,” notes University of Wyoming Extension Educator Mae Smith.

Although some seeds can be planted directly into the soil outside, others perform better if they are started inside and moved out into the garden once they have begun to grow.

“Cool season plants like Swiss chard, peas, garden beans, broccoli or lettuce like to germinate when it’s cold, so those will be plants we sow directly into the soil,” she comments.

However, warm season plants such as squash, tomatoes and peppers are likely to do better if they are started indoors.

To determine a seed starting timeline, growers can go online to to determine the average date of the last seasonal frost in their region.

“On our seed packets, there is usually a number of days for germination or how long it takes for the seedlings to emerge,” Smith adds, explaining that the last average frost date and germination period will help determine when seeds will be ready to move outdoors. “We can count back and see how far in advance we need to start our seeds.”

Starting out

Bearing in mind how many seeds come in each package is another consideration, as a whole packet usually has enough seeds to produce a large number of plants.

“If we think we can sustain our family on four cucumber plants, we might think about planting four to six cucumber seeds, instead of the whole package,” Smith suggests.

Starting plants for other people, large family sizes or preserving vegetables may be factors that growers consider if they plan on starting larger numbers of seeds.

“Next, we want to decide what we’re going to be planting our seeds in. There are a whole variety of things we can do. For example, many garden stores have handy seed starting kits,” she says.

Protecting seedlings

Seed starting kits include small packets of soil specifically designed for new seeds, making it easy to start different plants indoors.

“We want to start our seeds in a seed starting soil mix. This will be a little more expensive, but it’s crucial because it is sterile soil, and there won’t be diseases,” Smith adds.

She also recommends washing out old containers to prevent diseases that may hinder new plants as they grow. A mixture of one part bleach to nine parts water can be used to sterilize pots or containers that have been used before.

“The new plants are really susceptible to freezes, wind and drying out,” Smith continues, adding that keeping them covered will help protect them until they have grown stronger.


Once seeds are planted, they should be placed under lights that are placed closely over the soil. As the plants begin to emerge, the lights can be raised slowly to allow room for growth.

“If we put them on the windowsill, chances are our plants are going to get really tall, spindly and then eventually fall over, or they will really lean toward the light,” she explains.

Once plants have grown large enough, generally when they exhibit at least two true leaves, they can be gently transplanted into larger containers.

“We need to be very careful with the roots because they are tender and small at that point,” Smith warns.

Once the plants are large enough and the last hard frost of the season has likely passed, they can be moved outside.

Moving outside

“We want to go through a process called hardening off,” Smith notes. “The plants have lived in this beautiful microenvironment for maybe two months, and when we introduce them to the real Wyoming, the UV light can be too much for them.”

By placing the plants outside in a shady spot during the day, they can become accustomed to the outdoor weather gradually as they grow hardier.

“We want to pull the plants inside during the night and do that for a week or so until they get more time outside,” she continues.

Eventually the plants can be planted into the soil and monitored closely for the first few weeks to ensure they are not killed by frost or other extreme events.

“We want to be sure to protect them for a little while,” she says. “We can baby them for a little while until they are established.”

Smith spoke at WESTI Ag Days in Worland on Feb. 20.

Natasha Wheeler is editor of the Wyoming Livestock Roundup and can be contacted at

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