The Basics of Fertilizing

Frequently harvested crops like lettuce need regular fertilizing.

Most vegetables, especially fast-growing leafy ones that are harvested again and again, need fertilizer to replace nutrients.

Plants grow using energy from the sun combined with nutrients taken from the soil. Because the organic matter in soil holds nutrients like a sponge until they are needed by plants, soil that is fertile, well-drained, and regularly enriched with compost often holds a reasonable supply of plant nutrients. Unimproved, though, newly cultivated soil is usually low in organic matter, so it is also low in nutrients.

Bonnie Plants plant food hose-end sprayer makes fertilizing easy.

Feed your plants with liquid plant food at planting time, then every week or two afterward for a boost of nutrition. Bonnie Plant Food can be sprayed at the base of the plants to target the roots, or directly on the foliage.

All edible plants remove some nutrients from the soil, and some have such huge appetites that they will quickly exhaust the soil (and then produce a poor crop) without the help of fertilizer. Fertilizing is especially helpful early on, when plants are making fast new growth. You can mix a continuous-release fertilizer, such as Miracle-Gro Shake ‘N Feed, into individual planting holes, work it into furrows, or use a turning fork to mix it into beds. You can also apply a liquid fertilizer, such as Bonnie Herb, Vegetable & Flower Plant Food, every week or two for a fast-acting extra boost of nutrition.

Always follow the rates given on the fertilizer label when deciding how much to use. Too much fertilizer can be worse than too little! Overfed plants often grow huge, yet bear a light crop late in the season.

With experience, you will learn how to match fertilizer amounts with plants’ needs for your climate and soil. Onions, tomatoes, sweet corn, and vegetables grown in containers respond to special fertilizing techniques, but most crops grow well if you simply mix a balanced fertilizer into the soil as you set out the plants. Use the lists below to help determine the best method for feeding your favorite vegetables.

Light feeders often benefit from a small amount of starter fertilizer but require no additional feeding when grown in soil that has been enriched with compost.

  • Bush beans
  • Mustard greens
  • Peas
  • Southern peas
  • Turnips

Moderate feeders often need good drainage and moisture-holding mulch more than they need fertilizer. Avoid using organic fertilizers made primarily from processed manure when preparing the soil for beets, carrots, and other root crops. Manure can contribute to scabby patches on potato skins and forked roots in carrots and parsnips. Moderate feeders all respond well to liquid plant food.

  • Beets
  • Carrots
  • Okra
  • Pole beans
  • Potatoes
  • Sweet potatoes
Fertilizing provides plants like these tomatoes with lots of much-needed nitrogen.

Mixing fertilizer into the planting holes as you set out tomatoes and other heavy feeders helps ensure that the plants will find the nutrients they need at every stage of growth.

Heavy feeders are often highly productive plants, so a few minutes spent mixing in fertilizer before you set out plants is time well spent. Just don’t go overboard by applying too much! Plants often grow slowly in cool spring weather, so you won’t see the effects of feeding until the weather warms. Some heavy feeders also respond to second helpings later in the season (again, follow package directions), and all types will benefit from regular applications of liquid plant food.

  • Broccoli
  • Brussels sprouts
  • Cabbage
  • Cantaloupe
  • Cauliflower
  • Corn
  • Cucumbers
  • Eggplant
  • Kale
  • Kohlrabi
  • Onions
  • Peppers
  • Rhubarb
  • Squash
  • Tomatoes
  • Watermelon