Starting Seeds with Patience
April 3, 2021
Partial reprint by Dr. Marisa Thompson and Dr. Curtis Smith!
Starting plants from seed can be confusing. Too little water, and they dry and die. Too much, and all of a sudden, you’re farming algae. Patience and attentiveness are required during this delicate phase of seedling growth, especially if some seeds are sprouting while others take their sweet time. Visit the blog version of this column at Desert Blooms for more seed starting tips, and check out the recorded Ready, Set, GROW! gardening webinar “Indoor Seed Starting” with NMSU Bernalillo County Extension Program Manager Nissa Patterson at Ready, Set, Grow!.
I know it’s been warm out, but be patient transplanting outdoors, too. Remember that your area's average last frost date is based on the average over a specific number of years and that the latest frost date on record might be a month or more after the average date. For example, according to spring freeze data posted by National Oceanic and Atmospheric Administration (NOAA) and the National Weather Service, the last average frost date for Santa Rosa, NM is April 18, but the latest on record was May 19, 2000. And temps dropped to 28 degrees that night.
Don't let seeds dry when they are germinating!
Reprinted column from March 14, 2009 by retired NMSU Extension Horticulture Specialist Dr. Curtis Smith.
How critical is it to give native plant seeds a lot of water to get them to germinate? I planted some seeds of native wildflowers, watered them once, and only a few came up.
The time during which a seed is germinating is a critical period for moisture. If the seed begins to germinate and dries out, it will die. Some plants can survive on a single irrigation if the soil holds enough moisture and natural rainfall comes when needed. In very sandy soils that do not hold much water, the seeds can dry quickly and die. A clay soil will hold more moisture and give the seedling a better chance to establish.
Some seeds native to desert regions have a "chemical rain gauge" in the seed coat or fruit covering around the seed. This chemical prevents germination while it is present but is washed away if there is adequate moisture. The quantity of moisture required to wash this chemical away is the amount of moisture that is sufficient to allow the seed to germinate and grow. Some seeds may have more of this inhibitor so that they require more moisture, and others have less so that they can germinate more quickly. Those that germinate quickly are counting on another precipitation or irrigation event to sustain them. Those that have more chemical inhibitors are better prepared to grow if there is no new precipitation event in the near future. This chemical inhibition of germination is an insurance policy to ensure that at least a few of the seeds will germinate at the right time.
Our common garden flowers and vegetables often do not have these inhibitors. They were bred so that we could plant the seed and have uniform germination. Wildflower seeds may still exhibit germination spread over time because they may have these inhibitors. Knowing this helps you understand that consistent irrigation is necessary for many of the flowers and vegetables we plant.
Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: firstname.lastname@example.org, office: 505-865-7340, ext. 113.
Please copy your County Extension Agent and indicate your county of residence when you submit your question!