Residents in the Central San Joaquin Valley are encouraged to begin spring gardening tasks as outlined by UC Master Gardener Terry Lewis. March is highlighted as a key time for transitioning from winter planning to active work in the garden.
Gardeners are advised to continue spraying fruit trees and apply fungicide to apple and cherry trees. Weed management should be handled through hand-pulling, hoeing, or careful herbicide application on calm days to prevent drift.
Pruning is recommended after bloom for spring-flowering shrubs, trees, and vines. Ornamental grasses and ground covers such as lantana, verbena, Asian jasmine, and vinca should be sheared back. Hedges can also be shaped at this time.
Fertilizing guidance includes applying one third of the needed fertilizer amount to deciduous fruit and nut trees now. Acid-loving plants should only be fertilized after blooming with appropriate products. Blooming ornamental deciduous trees should receive fertilizer two or three weeks after they finish blooming.
For planting, seeds for summer vegetables can be sown this month, but it is suggested that tomatoes, summer squash, and beans be planted later in spring. Recommended annuals include impatiens and alyssum (Lobularia). Bulbs such as tiger flower (Tigridia), fruits like daikon and melon, perennials including Lenten rose (Helleborus orientalis), coral bells (Heuchera), gayfeather (Liatris), as well as trees like California lilac (Ceanothus) and citrus are also suitable for planting now.
Currently blooming plants include dianthus and Lenten rose among annuals and perennials; grape hyacinth (Muscari) and ‘Paper White’ narcissus among bulbs; saucer magnolia among trees; along with lettuce, onions, parsley, parsnips, and peas in the vegetable category.
The advisory notes: “Protect tomatoes, peppers and eggplant from a late frost by using hot caps or floating row covers.”
This information was prepared by UC Master Gardener Terry Lewis with content adapted from A Gardener’s Companion for the Central San Joaquin Valley. The public is invited to submit questions or photos regarding garden issues to the Fresno County Master Gardeners Helpline.
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