The best size grow bag for vegetables depends on the specific vegetable you want to grow and the space you have available. Generally, larger grow bags (e.g. 20-30 gallons) are better for most vegetables as they allow for deeper roots and provide more room for growth like carrots, pumpkins, squash, melons, okras, etc. However, some smaller vegetables like lettuce, spinach, and radishes can be grown in smaller grow bags (5-10 gallons) if you have limited space. Anything smaller like 1-3 gallons are ideal for herbs like garlics, onions, cilantros etc.
When choosing a grow bag, it's also important to consider the drainage and aeration of the soil, as well as the amount of sunlight your growing area receives. If you're not sure which size is best for your needs, you may want to consult a gardening expert or do some research online to find recommendations for the specific vegetables you want to grow or just give 247Garden a call.
You can also consult this list
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