First Frost & Freeze Dates for Berwyn Heights/College Park/Greenbelt

Predicting first frost or freeze dates is like predicting next months weather -- Good luck with that.  What we have are estimates based on historical data.  In another blog post I discussed the last frost or freeze dates.  Well, the same reasoning applies to this estimate of the first frost or freeze dates.  These dates are published by the National Gardening Association for the College Park ZIP Code 20740.

Temperature 10% 20% 30% 40% 50% 60% 70% 80% 90%
First 16° 1-Dec 7-Dec 11-Dec 14-Dec 18-Dec 21-Dec 24-Dec 29-Dec 3-Jan
First 20° 17-Nov 24-Nov 29-Nov 3-Dec 7-Dec 11-Dec 16-Dec 21-Dec 28-Dec
First 24° 2-Nov 7-Nov 11-Nov 15-Nov 18-Nov 21-Nov 25-Nov 29-Nov 4-Dec
First 28° 16-Oct 21-Oct 24-Oct 28-Oct 30-Oct 2-Nov 5-Nov 9-Nov 14-Nov
First 32° 9-Oct 13-Oct 17-Oct 19-Oct 22-Oct 25-Oct 27-Oct 31-Oct 4-Nov
First 36° 30-Sep 4-Oct 7-Oct 10-Oct 12-Oct 15-Oct 17-Oct 20-Oct 25-Oct

So, on average the 50/50 chance of first frost (30 degree temperature) occurs on October 12 and the 90% chance of frost occurs on October 25.  Can you get your remaining vegetables harvested before the first frost or freeze.  Covering your plants overnight with frost blanket or old sheet can buy you a degree or two of protection.  Instead of frost fabric, I use inexpensive twin-sized fleece blankets that I bought expressly to protect plants from frost and freezing.