Our advanced 2019 cotton crop has begun to show off in August this year with a good amount of boll opening all over the region and particularly in the first planted, determinant varieties. One of my North Carolina buddies said it is the earliest good cotton crop he has ever had.
- Assessing when to defoliate will rely on the traditional methods of using nodes above cracked boll and tan seed coats in top bolls.
- Once a field has at least one open boll on most plants, we should be within 2-3 weeks of defoliating that field.
- Since some fields were in that condition last week and several are getting like that this week, it is easy to predict that we will have some acreage ready to defoliate 10 days earlier than normal.
- 2100 heat units is another maturity benchmark for our region and cotton planted May 1st should hit that around September 9th.
- We normally set our crop on about 10 fruiting branches, and once the bottom boll opens, it will advance 2 or 3 nodes up per week depending on heat. In two warm weeks, you’ll have bolls open on the bottom 6 fruiting branches and the next 3-4 will be mature (that is where the 2/3’s open rule comes from).
- The trick is going to be in determining whether to wait on late blooms if they stayed on the plant. Some strong fields and aggressive fertility programs hold a lot of top crop with decent boll numbers on fruiting branch node 11 to 13 but this is not normal most years.
- Bolls set from the first week of August will need until the 3rd week of September to mature. Mid-August set bolls will need to wait until early October and Late August blooms do not have mature bolls until mid-October.
- Even the late May planted cotton should reach full maturity in the first half of October.