If you live makai and you already started your bell peppers, you can look forward to harvesting in winter and early spring. There’s still time to take advantage of the cooler weather that promotes better fruiting. Bell peppers don’t always set fruit when temps rise above 90˚ F. If you live up mauka, however, you might need to wait until spring/early summer for ideal growing conditions in your area.
Buy transplants from a nursery, or start bells from seed and transplant them into well-draining, fertile planting media at about 6-8 weeks old. Water daily. Wait about a week after transplanting and then apply weekly a liquid fertilizer—I like fish emulsion/kelp extract. Keep the planting area free from weeds because they tend to attract insects that pass on mosaic disease to peppers. Be on the lookout for aphids, white flies, mites, thrips, leaf miners and pepper weevils.
Insecticidal soap, homemade or store-bought, is effective on soft-bodied insects. Also, try aluminum foil mulch to suppress weeds and repel aphids. The foil reflects light up onto the underside of leaves where aphids like to hang out, and that bums them out. If you have only a few plants you can use heavy duty aluminum foil to cover area around the base of plants, but if you can find it aluminum foil coated paper is usually less expensive if you need a lot. See an example here.