Address any underlying issues such as soil quality, sunlight exposure, watering issues, pests, diseases, and pruning practices. Select appropriate blackberry varieties for your climate and soil conditions; some of those include Prime-Ark Traveler, Prime-Ark Freedom, Osage, Natchez or Triple Crown.
Blackberry bushes prefer well-drained, slightly acidic soil. If the soil is too compacted, lacks nutrients, or is too alkaline (get a soil pH kit with numeric results), the blackberry bush may struggle to grow. Blackberry bushes require plenty of sunlight (full sun) to thrive so if yours is planted in a location with insufficient sunlight, such as deep shade, they may not grow well. Blackberry bushes need regular watering, especially during dry periods. If they are not receiving sufficient/consistent waterings or if they are overwatered, they may not grow properly. Monitor for typical pests: aphids, spider mites, and fungal infections. Pruning is important for blackberry bushes to encourage new growth and fruit production. If the bush is not pruned properly or at the right time (some prune on current season canes and other bushes produce on previous season's canes) , it may become overcrowded, which can inhibit growth. Finally, ensure it was planted correctly. If it was planted too deeply or too shallow, it may not establish well.
