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Crabgrass Germination Prediction (GDD 50)
through Fri, May. 8. 2026

 

GDD Total: 537 (Base 50) through Fri, May. 8, 2026

  

Greencastle, IN

        

Forecast »

“Flashback” to 2025

5/5

5/6

5/7

5/8

5/9

5/10

5/11

5/12

5/13

5/14

5/15

5/16

5/17

Done

1401

Late

601

Germination

200

Early

100

Under

0

 

Generously Supported By:



Tabular Data

Daily GDD accumulation for various base temperature models in 2025 & 2026

2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 39° 54° 25 15 5 0 0
02-16 32° 58° 48 28 8 0 0
02-17 38° 53° 71 41 11 0 0
02-18 50° 68° 108 68 28 9 4
02-19 49° 64° 143 93 43 15 5
02-20 32° 57° 165 105 45 15 5
02-21 24° 36° 173 105 45 15 5
02-22 18° 27° 173 105 45 15 5
02-23 15° 28° 173 105 45 15 5
02-24 17° 39° 179 105 45 15 5
02-25 35° 50° 199 115 45 15 5
02-26 31° 49° 218 124 45 15 5
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 33° 63° 244 140 51 15 5
02-28 35° 59° 269 155 56 15 5
03-01 30° 38° 281 157 56 15 5
03-02 29° 39° 293 159 56 15 5
03-03 36° 45° 311 167 56 15 5
03-04 44° 58° 340 186 65 16 5
03-05 54° 60° 375 211 81 24 8
03-06 59° 77° 421 247 106 41 21
03-07 44° 67° 454 270 120 47 21
03-08 38° 57° 480 286 125 47 21
03-09 43° 66° 513 309 138 51 21
03-10 63° 75° 560 346 165 70 35
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 38° 71° 592 368 177 74 35
03-12 31° 48° 609 375 177 74 35
03-13 42° 55° 636 392 184 74 35
03-14 36° 51° 657 403 185 74 35
03-15 43° 69° 691 427 199 80 36
03-16 25° 42° 702 428 199 80 36
03-17 17° 25° 702 428 199 80 36
03-18 23° 51° 717 433 199 80 36
03-19 38° 70° 749 455 211 84 36
03-20 49° 79° 791 487 233 98 45
03-21 44° 74° 828 514 250 108 49
03-22 42° 83° 869 545 271 120 57
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 33° 45° 886 552 271 120 57
03-24 30° 54° 906 562 271 120 57
03-25 39° 70° 938 584 283 124 57
03-26 57° 81° 985 621 310 144 71
03-27 36° 55° 1009 635 314 144 71
03-28 29° 50° 1026 642 314 144 71
03-29 38° 66° 1056 662 324 145 71
03-30 54° 77° 1100 696 348 161 82
03-31 61° 79° 1148 734 376 181 97
04-01 46° 71° 1184 760 392 190 100
04-02 45° 78° 1224 790 412 201 107
04-03 64° 76° 1272 828 440 221 122
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 45° 70° 1308 854 455 229 125
04-05 41° 52° 1332 868 460 229 125
04-06 40° 56° 1358 884 466 229 125
04-07 34° 49° 1378 894 466 229 125
04-08 37° 71° 1410 916 478 233 125
04-09 55° 76° 1453 949 501 249 135
04-10 51° 68° 1491 977 519 258 139
04-11 40° 70° 1524 1000 532 263 139
04-12 56° 79° 1569 1035 557 280 152
04-13 66° 80° 1620 1076 588 304 170
04-14 68° 80° 1672 1118 621 328 189
04-15 67° 78° 1723 1159 651 350 206
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 61° 76° 1769 1195 677 369 220
04-17 54° 81° 1815 1231 703 386 233
04-18 45° 72° 1851 1257 719 395 236
04-19 35° 58° 1876 1272 724 395 236
04-20 33° 58° 1900 1286 728 395 236
04-21 45° 77° 1938 1314 747 405 242
04-22 60° 79° 1986 1352 774 425 257
04-23 55° 82° 2033 1389 801 444 270
04-24 57° 72° 2076 1422 824 459 280
04-25 53° 72° 2116 1452 844 471 288
04-26 51° 73° 2156 1482 864 483 295
04-27 56° 66° 2195 1511 883 494 301
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 56° 63° 2233 1539 901 504 305
04-29 49° 63° 2267 1563 915 510 307
04-30 39° 59° 2294 1580 922 510 307
05-01 45° 54° 2321 1597 929 510 307
05-02 41° 53° 2346 1612 934 510 307
05-03 38° 62° 2374 1630 942 510 307
05-04 52° 73° 2414 1660 962 523 314
05-05 47° 66° 2449 1685 977 529 316
05-06 44° 58° 2478 1704 986 530 316
05-07 37° 61° 2505 1721 993 530 316
05-08 47° 66° 2539 1745 1007 537 317
05-09 53° 72° 2580 1776 1028 549 325
2026Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 52° 66° 2617 1803 1045 558 329
05-11 45° 70° 2652 1828 1060 565 331
05-12 44° 77° 2691 1857 1079 576 337
05-13 57° 68° 2731 1887 1099 588 344
05-14 44° 68° 2765 1911 1113 594 345
05-15 46° 70° 2801 1937 1129 602 348
05-16 60° 85° 2851 1977 1159 624 365
05-17 64° 86° 2904 2020 1192 649 385
05-18 69° 88° 2960 2066 1229 678 408
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-15 33° 41° 15 5 0 0 0
02-16 18° 35° 19 5 0 0 0
02-17 5° 18° 19 5 0 0 0
02-18 7° 16° 19 5 0 0 0
02-19 12° 19° 19 5 0 0 0
02-20 2° 19° 19 5 0 0 0
02-21 5° 26° 19 5 0 0 0
02-22 12° 33° 20 5 0 0 0
02-23 20° 45° 31 6 0 0 0
02-24 33° 53° 52 17 1 0 0
02-25 35° 60° 77 32 7 0 0
02-26 34° 61° 103 48 12 0 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
02-27 37° 55° 127 62 16 0 0
02-28 32° 66° 154 79 23 0 0
03-01 21° 44° 165 80 23 0 0
03-02 14° 36° 168 80 23 0 0
03-03 26° 52° 185 87 23 0 0
03-04 45° 65° 218 110 36 5 0
03-05 32° 55° 239 121 38 5 0
03-06 30° 41° 253 125 38 5 0
03-07 32° 48° 271 133 38 5 0
03-08 32° 50° 290 142 38 5 0
03-09 32° 59° 313 155 41 5 0
03-10 34° 68° 342 174 50 6 0
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-11 46° 72° 380 201 67 15 4
03-12 41° 73° 415 226 82 22 6
03-13 43° 76° 452 254 100 32 10
03-14 52° 79° 495 287 123 47 21
03-15 57° 70° 537 319 145 61 30
03-16 33° 57° 560 332 148 61 30
03-17 27° 52° 578 339 148 61 30
03-18 44° 75° 615 367 165 70 34
03-19 49° 67° 651 393 181 78 37
03-20 33° 47° 669 401 181 78 37
03-21 27° 56° 689 410 181 78 37
03-22 38° 52° 712 423 184 78 37
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
03-23 36° 46° 731 433 184 78 37
03-24 36° 53° 754 445 187 78 37
03-25 36° 47° 773 455 187 78 37
03-26 32° 55° 795 466 188 78 37
03-27 41° 55° 821 482 194 78 37
03-28 50° 80° 864 516 217 93 47
03-29 61° 71° 908 550 242 110 58
03-30 57° 73° 951 583 264 124 68
03-31 36° 58° 976 598 269 124 68
04-01 30° 54° 996 608 270 124 68
04-02 47° 80° 1038 640 292 138 77
04-03 51° 65° 1074 666 308 146 80
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-04 46° 55° 1103 684 316 147 80
04-05 44° 59° 1132 704 326 148 80
04-06 39° 45° 1152 714 326 148 80
04-07 32° 56° 1174 726 327 148 80
04-08 28° 43° 1187 729 327 148 80
04-09 32° 49° 1206 738 327 148 80
04-10 40° 63° 1236 757 337 150 80
04-11 40° 51° 1259 771 340 150 80
04-12 31° 58° 1282 784 343 150 80
04-13 45° 68° 1316 808 358 156 82
04-14 53° 73° 1357 839 379 169 90
04-15 43° 55° 1385 856 386 169 90
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-16 36° 61° 1411 873 393 169 90
04-17 45° 65° 1444 896 405 174 90
04-18 56° 77° 1489 931 430 191 102
04-19 54° 73° 1530 962 452 204 110
04-20 51° 75° 1572 993 473 218 118
04-21 51° 70° 1610 1022 492 228 124
04-22 41° 71° 1645 1046 506 235 125
04-23 50° 77° 1686 1078 527 248 134
04-24 52° 82° 1731 1113 553 265 146
04-25 55° 71° 1772 1144 574 278 154
04-26 45° 59° 1802 1164 584 280 154
04-27 43° 67° 1835 1187 596 285 154
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
04-28 53° 82° 1881 1223 622 303 167
04-29 58° 78° 1927 1259 648 321 180
04-30 49° 70° 1965 1286 666 331 184
05-01 63° 72° 2010 1322 692 348 197
05-02 58° 70° 2052 1354 714 362 206
05-03 54° 63° 2089 1381 730 371 210
05-04 46° 51° 2115 1397 737 371 210
05-05 49° 60° 2148 1420 749 375 210
05-06 46° 70° 2184 1446 765 383 213
05-07 52° 76° 2226 1477 787 397 221
05-08 57° 72° 2268 1510 809 411 231
05-09 45° 67° 2302 1534 823 417 231
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-10 44° 77° 2341 1562 842 428 237
05-11 47° 80° 2382 1594 864 442 246
05-12 60° 77° 2429 1630 890 460 259
05-13 60° 78° 2476 1668 917 479 274
05-14 62° 80° 2525 1707 947 501 290
05-15 65° 87° 2579 1751 981 527 311
05-16 64° 85° 2631 1793 1013 551 330
05-17 59° 69° 2673 1825 1035 565 339
05-18 51° 73° 2713 1855 1055 577 346
05-19 53° 76° 2756 1887 1077 591 355
05-20 56° 74° 2799 1920 1100 606 365
05-21 55° 63° 2836 1948 1117 615 370
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
05-22 50° 56° 2867 1968 1128 618 370
05-23 41° 67° 2899 1991 1140 622 370
05-24 50° 69° 2937 2018 1158 632 374
05-25 53° 64° 2973 2045 1175 641 378
05-26 50° 70° 3011 2073 1193 651 383
05-27 57° 70° 3053 2105 1214 664 391
05-28 59° 70° 3095 2137 1237 679 401
05-29 52° 70° 3134 2166 1256 690 407
05-30 58° 74° 3179 2200 1280 706 418
05-31 60° 72° 3222 2234 1304 722 429
06-01 46° 75° 3261 2263 1322 732 435
06-02 50° 81° 3304 2296 1346 748 445
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-03 62° 86° 3356 2338 1378 772 464
06-04 70° 85° 3412 2384 1414 800 487
06-05 67° 74° 3461 2422 1442 820 502
06-06 66° 76° 3510 2461 1471 841 518
06-07 62° 75° 3556 2498 1498 860 532
06-08 63° 79° 3605 2537 1526 880 548
06-09 60° 76° 3651 2573 1553 899 561
06-10 55° 75° 3695 2606 1576 914 571
06-11 57° 83° 3742 2644 1604 934 586
06-12 63° 81° 3792 2684 1634 956 603
06-13 68° 79° 3844 2726 1666 980 622
06-14 69° 77° 3895 2767 1696 1002 639
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-15 66° 78° 3945 2807 1726 1024 656
06-16 67° 80° 3997 2849 1758 1048 675
06-17 70° 83° 4051 2893 1793 1075 697
06-18 70° 86° 4107 2939 1829 1103 720
06-19 68° 82° 4160 2982 1862 1128 740
06-20 65° 83° 4212 3024 1894 1152 759
06-21 71° 91° 4271 3073 1932 1182 785
06-22 75° 91° 4332 3124 1974 1216 813
06-23 74° 92° 4393 3175 2015 1249 841
06-24 75° 90° 4454 3226 2056 1282 869
06-25 74° 90° 4514 3276 2095 1313 896
06-26 74° 92° 4575 3327 2136 1346 923
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
06-27 75° 89° 4635 3377 2176 1378 950
06-28 74° 88° 4694 3425 2215 1409 976
06-29 71° 83° 4749 3471 2250 1436 998
06-30 72° 87° 4807 3518 2288 1466 1023
07-01 71° 85° 4863 3564 2324 1494 1046
07-02 65° 85° 4916 3608 2357 1519 1066
07-03 68° 88° 4972 3654 2393 1547 1090
07-04 67° 89° 5028 3700 2430 1576 1113
07-05 68° 90° 5086 3747 2467 1605 1137
07-06 72° 90° 5145 3797 2506 1636 1163
07-07 69° 80° 5198 3839 2539 1661 1183
07-08 61° 86° 5249 3881 2571 1685 1202
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-09 71° 85° 5305 3927 2607 1713 1225
07-10 68° 87° 5361 3973 2642 1740 1247
07-11 71° 90° 5419 4021 2681 1771 1273
07-12 75° 86° 5478 4070 2720 1802 1299
07-13 69° 87° 5534 4116 2756 1830 1322
07-14 69° 86° 5590 4161 2791 1857 1344
07-15 73° 86° 5647 4209 2828 1886 1369
07-16 72° 88° 5705 4257 2867 1917 1394
07-17 70° 86° 5761 4303 2902 1944 1417
07-18 69° 85° 5816 4348 2938 1972 1439
07-19 71° 82° 5871 4392 2972 1998 1460
07-20 73° 87° 5928 4440 3010 2028 1485
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
07-21 74° 80° 5984 4486 3045 2055 1507
07-22 67° 85° 6038 4530 3079 2081 1529
07-23 70° 90° 6096 4578 3117 2111 1553
07-24 76° 92° 6158 4629 3159 2145 1582
07-25 77° 88° 6218 4680 3199 2177 1610
07-26 75° 89° 6278 4730 3240 2210 1637
07-27 74° 89° 6338 4780 3279 2241 1663
07-28 72° 89° 6397 4828 3318 2272 1689
07-29 74° 92° 6458 4879 3359 2305 1717
07-30 72° 90° 6516 4928 3398 2336 1743
07-31 69° 81° 6569 4971 3430 2360 1762
08-01 62° 77° 6616 5008 3458 2380 1777
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-02 59° 77° 6662 5044 3484 2398 1790
08-03 59° 80° 6709 5081 3511 2417 1804
08-04 66° 76° 6758 5120 3539 2437 1819
08-05 65° 81° 6809 5161 3571 2461 1838
08-06 65° 85° 6862 5204 3603 2485 1858
08-07 67° 87° 6917 5249 3638 2512 1879
08-08 68° 88° 6973 5295 3674 2540 1902
08-09 70° 88° 7030 5341 3711 2569 1926
08-10 70° 88° 7086 5388 3748 2598 1950
08-11 70° 88° 7143 5435 3785 2627 1974
08-12 71° 86° 7200 5481 3821 2655 1997
08-13 67° 85° 7254 5525 3855 2681 2018
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-14 67° 87° 7308 5570 3890 2708 2040
08-15 69° 89° 7366 5617 3927 2737 2064
08-16 72° 93° 7426 5668 3967 2769 2092
08-17 70° 89° 7484 5716 4005 2799 2116
08-18 72° 86° 7541 5763 4043 2829 2141
08-19 72° 87° 7599 5811 4080 2858 2165
08-20 68° 79° 7650 5852 4112 2882 2184
08-21 66° 78° 7700 5892 4141 2903 2201
08-22 58° 76° 7745 5927 4167 2921 2213
08-23 57° 79° 7791 5963 4193 2939 2226
08-24 57° 74° 7835 5997 4216 2954 2236
08-25 53° 71° 7875 6027 4236 2966 2243
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
08-26 48° 72° 7913 6055 4254 2976 2248
08-27 49° 75° 7953 6085 4274 2988 2255
08-28 55° 79° 7998 6119 4299 3005 2267
08-29 55° 76° 8041 6153 4323 3021 2278
08-30 53° 78° 8085 6186 4346 3036 2288
08-31 53° 77° 8127 6219 4369 3051 2298
09-01 53° 80° 8172 6254 4394 3068 2310
09-02 54° 83° 8219 6290 4420 3086 2323
09-03 52° 80° 8263 6324 4444 3102 2334
09-04 53° 69° 8302 6354 4463 3113 2340
09-05 53° 73° 8343 6385 4484 3126 2348
09-06 50° 69° 8380 6412 4502 3136 2353
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-07 48° 70° 8417 6439 4519 3145 2357
09-08 43° 73° 8453 6465 4534 3152 2359
09-09 46° 77° 8493 6494 4554 3164 2366
09-10 56° 83° 8540 6532 4582 3184 2381
09-11 57° 85° 8589 6571 4611 3205 2397
09-12 57° 85° 8639 6610 4640 3226 2413
09-13 58° 81° 8686 6648 4668 3246 2428
09-14 64° 88° 8740 6692 4701 3271 2449
09-15 62° 88° 8793 6735 4734 3296 2469
09-16 61° 86° 8845 6776 4766 3320 2487
09-17 55° 87° 8893 6815 4795 3341 2503
09-18 57° 88° 8944 6856 4825 3363 2520
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55
09-19 58° 87° 8995 6897 4856 3386 2538
09-20 61° 87° 9047 6939 4888 3410 2557
09-21 64° 82° 9098 6980 4919 3433 2575
09-22 64° 72° 9144 7016 4945 3451 2588
09-23 62° 80° 9193 7055 4974 3472 2604
09-24 64° 78° 9242 7094 5003 3493 2621
09-25 59° 75° 9287 7129 5028 3510 2632
09-26 53° 79° 9331 7163 5053 3527 2644
09-27 53° 84° 9378 7199 5079 3545 2657
09-28 56° 87° 9427 7239 5109 3567 2674
09-29 57° 88° 9478 7280 5139 3589 2691
09-30 60° 85° 9528 7320 5170 3612 2709
2025Lo
(F)		Hi
(F)		GDD
22		GDD
32		GDD
42		GDD
50		GDD
55

 

Latest Updates

February 16th, 2026Welcome to the 2026 GDD Tracking Season

Although Punxsutawney Phil saw his shadow predicting six more weeks of winter, GDDTracker will start counting on February 15. Spring is when GDDTracker receives the most attention for alerting turfgrass managers of optimal application timing windows for suppressing annual bluegrass seedheads and crabgrass preemergence applications. As spring turns to summer, there are several models that may be helpful throughout the season including the early season dollar spot DMI timer and the Smith-Kerns dollar spot prediction model. To learn about all the available models, click on the "About" tab at the top of the screen. Thanks for your continued support and use of GDDTracker and best wishes for a successful 2026!


 

March 18th, 2024Timing crabgrass preemergence applications in spring

Don't miss this update from from Kevin Frank regarding timing of crabgrass preemergence herbicides.


 

 

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