How Late Can Small Grains be Planted in the Spring?
Due to high precipitation combined with comparatively cooler weather conditions in April, planting of spring small grains is much delayed this year. According to USDA-NASS crop progress report of April 29th, only 12% of spring wheat is planted in South Dakota (SD), significantly lower than last year’s 83% and 63% of five-year average. Same situation is true for oats. The report shows that only 7% of oat is planted so far this year which is well below 82% of last year and five-year average of 68%.
Ideal Planting Dates
One of the rules of thumb while seeding spring small grains is to seed by third week of April to beat the heat during seed fill stage in June-July. Even though this year’s small grains planting has delayed quite significantly when compared with historical records, progressively better weather has encouraged many producers to start seeding their spring wheat and oats during the week of April 30th. One question these producers ask is: how late can we plant spring small grains, especially oats and spring wheat in SD?
Historically, small grains get seeded in the Southeast SD first (50% planted by April 15th) moving north with Northwest part of the state getting at least 50% acres planted by April 27th. The final planting date for spring wheat and oat crop insurance is May 5th for the south half and May 15th for the north half of SD.
What can we expect this year?
First thing to consider while planting any crop is soil temperature. Oat and spring wheat being cool season crops germinate at fairly low temperature and like to complete majority of the life cycle before extreme heat set into the month of July. If majority of small grain grown area in SD do not face prolonged period of extreme temperatures (more than 90F) during seed fill, the crops relatively tend to perform well.
One consideration can be to increase seeding rate by about 30% to compensate for possible loss of tillers due to warmer temperatures. Also, producers can opt for earlier maturing varieties while planting late in the spring. Maturity ratings and other important agronomic characteristics of wheat and oat varieties can be found in the most recent SDSU Extension variety trial results.
A substantial amount of oat crops in SD are harvested for forage and highest forage yield is usually obtained when the crop is planted early, however, the total biomass production is not impacted as badly as for grain when planted late.
Source: David Karki, iGrow