One of June's delights for me is just watching plants grow. The small annuals that have been set out in containers in mid to late May will begin expanding visibly and setting buds. So here is something that does need to be done. Water and fertilize container plants regularly. Liquid fertilizers with moderate levels of nitrogen work best for most container displays.
Many gardeners fertilize every three or four weeks to keep container plants looking good.
If you choose to fertilize more often, such as every two weeks, use the selected fertilizer at the strength suggested on the package. Use less fertilizers on some plants. Annual zonal geraniums, do not need a heavily-fertilized soil mix. Most culinary herbs such as rosemary and oregano also grow better without extra fertilizer. Hanging baskets need additional attention.