As winter lingers, many gardeners are looking for ways to get their hands dirty. Starting seeds indoors gives gardeners greater control over growing conditions, resulting in healthier, more resilient transplants.

“It’s fun to get a head start on the upcoming garden season by starting seedlings indoors,” said Aaron Steil, consumer horticulture specialist with Iowa State University Extension and Outreach.

To be successful, gardeners must provide the right conditions for seedlings to thrive and develop into stocky, resilient plants.

Time it right

Resist the urge to sow too early. Steil warns that seedlings started too soon often become lanky and transplant poorly. Check the seed packet for the recommended indoor growing period, then count backward from your frost‑free date to determine when to start.

In much of Iowa, planting of frost‑tender annuals and vegetables happens from late April to early May. Cool‑season crops that tolerate light frost can be planted a bit earlier, in early to mid-April, so they can be started indoors sooner. “It’s important to plan before you plant,” Steil noted.

Choose the right growing medium and containers

Start with a lightweight, porous and disease‑free seed‑starting mix. Steil recommends commercially prepared soilless germination mixes designed for seedlings. Sow seeds in flats, cell packs, peat pellets, soil blocks or repurposed containers. “What you use is up to you, as long as it is clean and has drainage holes,” he said.

Sow like a pro

Use new seeds packaged for the current season, as older seeds, especially those more than 2 or 3 years old, often germinate poorly. Seeds can be sown in rows in a flat or tray and carefully transplanted to individual containers when they develop true leaves. “This approach is good for small seeds or those with inconsistent germination rates,” said Steil. Alternatively, seeds can be sown directly into individual containers, sowing several seeds per pot and thinning them later. This approach is well-suited for larger seeds.

Check the seed packet for sowing depth. Many are planted 1/4 inch deep and can be placed on the soil surface and lightly covered to ensure they are at the right depth. Small, fine seeds or those that require light to germinate are planted at a depth of 1/8 inch or less. “For these seeds, place the seeds on the surface and gently press them into the germination medium to ensure good seed to soil contact,” advised Steil.

Provide the best growing conditions

After sowing, water from below by submerging the container until the medium is fully wet, then let it drain. This prevents the seeds from washing or dislodging.

“Warm soil temperatures promote better, faster germination,” Steil explained. “After emerging, the seedlings grow best in cooler temperatures around 65 F. This promotes stout, transplant‑ready plants.”

To maintain high humidity, cover the container with a clear dome or other covering, and water lightly only if the soil surface dries out. Remove the cover as soon as seeds germinate, and ensure good ventilation and air circulation to prevent damping‑off diseases.

After germination, provide 12–16 hours of bright light each day to prevent stretching or leaning. Even with a sunny window, seedlings often grow best under supplemental light. Keep them 6–12 inches above the plants and raise the grow lights as seedlings grow.

Care and prepare seedlings

When seedlings graduate from a germination tray to individual pots, transplant them into a well‑drained potting mix. Fertilize regularly with a 1/4‑strength water‑soluble all‑purpose fertilizer. This will help to produce stockier transplants, provided enough light is available. Keep the growing medium moist but not soggy, checking daily and watering thoroughly when the surface is dry to the touch.

About two weeks before planting day, harden seedlings by gradually introducing them to outdoor conditions. “Start by putting them outside on cloudy days or in a shaded location, then after a few days, move them into more light and exposure,” said Steil. This important step helps seedlings transition from the ideal conditions indoors to the bright sunlight, cool temperatures and windy conditions found outside.

For more information on starting seeds indoors, visit ISU Extension and Outreach Yard and Garden and related resources, including:

• How to Successfully Start Seed Indoors
• Guide to Starting Seed Indoors
• Germination Requirements for Annuals and Vegetables
• Growing Indoor Plants Under Supplemental Lights
• Yard and Garden: Iowa State University Extension and Outreach 

K-State horticulture expert says the presence of water in a natural space can benefit mental well-being.

Limited by space in your garden? Looking for a new project to enhance your space? Wanting to attract birds and pollinators to your garden?

Kansas State University horticulture expert Cynthia Domenghini suggests adding a water element to the garden.

“Preliminary research suggests the presence of water in a natural space can benefit mental well-being. The sound of running water helps reduce noise pollution and provides a relaxing escape,” Domenghini said. “Water attracts birds and other pollinators which also contribute to positive well-being. Whether a bubbling rock, pond or waterfall, sensory interests are piqued by waterscapes in the landscape.”

Domenghini said water features don’t have to be large and complex, making it a great weekend project consisting of a container, water tough or large flower pot to hold water, or creating a larger reservoir to invite wildlife.

“There are myriad designs of fountains and ponds that will fit into any size garden,” Domenghini said.

Consider accessibility, interactivity and maintenance when deciding how to incorporate a therapeutic water feature into your landscape, she adds.

“Though an isolated water feature can become a destination where visitors may venture to seek refuge, if it is too inconvenient to access it, the feature loses efficacy,” Domenghini said.

She recommends positioning a water feature close to pathways that are frequented regularly so more people can enjoy the benefits, also making it easier to monitor the feature for maintenance concerns.

When adding movement to the water feature, people can interact through the calming effect of the noise the waterscape makes. Depending on the type of feature, it may be possible to allow play in the waterscape, Domenghini said. Consider adding stepping stones up to the feature, but always consider safety and follow necessary precautions when adding a water feature to the landscape.

“Incorporating a water feature into the landscape will have limited benefits to well- being if it requires intense maintenance,” Domenghini said. “Enter into this project with the understanding of the required maintenance and start small as you learn the basics. Don’t allow this therapeutic feature to become a stress-inducer.”

Domenghini and her colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes and gardens. The newsletter is available to view online or can be delivered by email each week.

Interested persons can also send their garden and yard-related questions to Domenghini at [email protected], or contact your local K-State Research and Extension office.