Year round fertilizer
A local gardening centre is offering only one fertilizer they say can be used all year round. Is this possible for best results?
Without knowing the product's details, I can't say one way or another. Products like Hollytone, a weak, balanced organic fertilizer can be applied at different rates depending on the season and the target plant. Trees and shrubs don't need much fertilizer; a few inches of compost if usually enough. Annuals and vegetables have a faster growth rate and need a nitrogen boost mid summer, particularly tomatoes, corn and other "heavy feeders". Fertilizing in fall should be at half the normal rate and applied no later than 6 weeks before first frost is expected. This helps plants "shut down" and prepare for winter. Fertilizer too late in the season is one cause of winter die-back. This website has many articles on fertilizers and which and how much to use for different plants. https://www.gardeningknowhow.com/search?q=fertilizer