With adequate moisture and heat, this amount may be greater and it may coincide better with crop demand when seeding is delayed. While phosphorous is important for quick emergence and healthy roots, it becomes less important as the soil warms up. Increasing seeding rates can be of benefit with cereal crops that are planted this late in the year. A five to ten percent increase above typical seeding rates for every ten days planting is delayed beyond May 15th should be sufficient. Late planting also generally results in higher protein so that is another reason to keep the nitrogen in check if you are planting malt barley.
Flea beetles are out and about now so added protection there is advised, if possible.