No‐till farmers who want more from their cover crops (CCs) are delaying CC termination until the main crop is planted. Delaying termination can help dry wet soils and reduce erosion. This process is referred to as planting green (PG). We hypothesized that PG would (i) dry soil at main crop planting, but conserve soil moisture later in the growing season; (ii) reduce soil temperature; (iii) reduce slug damage on main crops; and (iv) not reduce main crop yield. This experiment was conducted in Pennsylvania between 2015 and 2017 to compare two CC termination dates: preplant killed (PK) and planting green (PG) in corn (Zea mays L.) and soybean [Glycine max (L.) Merr.]. Planting green increased CC biomass an average of 94% and 94 to 181% compared to PK preceding corn and soybean, respectively. Soil was 7 to 24% drier and 0.9°C cooler at corn planting, and 8% drier and 0.7 to 2.4°C cooler at soybean planting in PG compared to PK. Slug damage was not different, lower, or higher in PG corn, and not different or lower in PG soybean compared to PK. Corn yield was reduced and not impacted by PG in higher and lower yielding environments, respectively. Soybean yield was stable across locations, and not affected by cover crop termination date. We concluded that corn was more vulnerable to yield losses from conditions created by PG than soybean; therefore, growers who desire potential benefits and lower risk from PG should first consider soybean. Core Ideas Planting green refers to planting the main crop into a living cover crop. Planting green increased cover crop biomass by 94% in corn and by 94 to 181% in soybean. Planting green dried the soil at main crop planting. Planting green cooled soil 0.7 to 2.4°C at planting. Soybean yield was not influenced by planting green; corn yield was reduced.

Some farmers who use cover crops (CCs) have moved from CC preplant kill (PK) to delayed CC termination, called planting green (PG). We conducted a study to explore if soil conditions and crop production can be optimized by manipulating winter cereal rye (Secale cereal L.) seeding rate and spring N topdress rate for these two termination times. Treatments were arranged in a split‐split plot, randomized complete block design with four replications for three years at two Pennsylvania locations. Main plots were seeding rate (34, 67, and 134 kg ha−1, or 1x, 2x, and 4x, respectively), subplots were termination timing (PK and PG), and sub‐subplots were N rate (34 and 67 kg ha−1, or low and high, respectively). Planting green nearly doubled rye biomass at both sites, and at Landisville the high N rate accumulated 17% more biomass than the low N rate, while there was no biomass N rate effect in PK. Soil in PG was 7–15% drier at planting, up to 7% wetter later, and up to 0.9–1.3 °C cooler compared with PK at both sites. Soybean (Glycine max L.) yield was reduced by 3–4% when PG was paired with the high N rate across seeding rates at Rock Springs and with the 1x seeding rate at Landisville compared with other treatment combinations. Soybean population was not impacted by treatments. We conclude rye seeding and N topdress rates of 34 kg ha−1 in PG can maintain similar conditions and soybean yield equivalent to PK, thereby reducing seed and N costs.