You can start cucumber seeds indoors for planting outdoors once the threat of frost passes. Starting the seeds indoors ensures that you only plant seeds that have germinated and will result in plant. Cucumbers grow well in the warm season and they grow quickly without a lot of care and maintenance.Starting your own seeds will allow you to grow many plants without spending money on nursery-grown seedlings.tarting the seeds indoors ensures that you only plant seeds that have germinated and will result in plant. Cucumbers grow well in the warm season and they grow quickly without a lot of care and maintenance.