UC Master Gardeners, Santa Clara County, CA
University of California
UC Master Gardeners, Santa Clara County, CA

Growing Great Tomatoes

Garden Help >Vegetables > Tomatoes

SITE SELECTION

Tomatoes do best planted in full sun all day, although they will usually produce some crop with less. If your plants have had symptoms of disease in previous years, it is important to plant in soil that has not grown tomatoes or their relatives such as peppers or eggplants for three or more years.

SOIL PREPARATION

Depending on your soil, tomatoes often do best with only a generous application of compost mixed well into the planting area as much of our Santa Clara Valley floor is quite fertile. Excess nitrogen can result in getting more foliage at the expense of fruit. Just planting into plain soil can produce plants that are 7–8' tall and 3–4' wide for some of the larger, more robust indeterminate types.

PLANTING

After purchasing seedlings in 4" pots, you can either transplant directly into the ground or transplant into a larger container like a one-gallon and let grow in a warm, protected, sunny location for 2–3 more weeks.

  • Harden plants off by gradually acclimating plants to outdoor conditions for 4–7 days before transplanting into the ground in late April–early May.
  • Remove lower leaves and plant deeper than plant was in original container. It works well to lay tomato horizontally in planting hole so stem is 2–4" beneath soil with just the growing tip above ground. Roots will form at leaf nodes, which are where leaves had been or are growing.

SUPPORTING THE PLANTS

Provide hefty support for indeterminate (tall) types of tomato plants. Example: make a 5–6' tall cage out of concrete reinforcing wire. Be sure the mesh is large enough, 6" square, so you can reach in and harvest the ripe fruit. By making varying diameters such as 18", 20" and 22", the cylinder cages can be nested one inside the other for neater storage. These cages will need to be further supported with a stake such as rebar or a 2" x 2" wood stake at least 4' tall pounded in next to cage and wired to it. Put the cage on soon after planting so it is easy to get over plant.

  • Bush or determinate types may need no support or just the lightweight 3' tall cages widely available.
  • Semi-determinate types, which usually reach about 4' tall, will do fine in the medium-weight 4' tall tomato cages.
  • Another great, easy way to support tomatoes is by pounding in 7' metal T-stakes about 6' apart and stretching the concrete reinforcing wire flat like a fence between the stakes. As the tomatoes grow, you weave the tomato foliage into the fence.

GROWING YOUR TOMATOES

Irrigate about twice a week during the early part of the season, reducing water by as much as 50% as fruit begins to ripen to reduce cracking and subsequent rot and to intensify flavor.

  • Pinch off small side shoots in leaf axils before they are 6" long when necessary to reduce overcrowding in cage.
  • Pinch all growth that goes more than a foot above cage so it doesn't flop over and shade out rest of plant.

MOST COMMON TOMATO PROBLEMS

Most common and still least recognized is the tomato russet mite which causes plants to get dead leaves starting at bottom of plant and moving upwards. Stem takes on a bronzy appearance. It is easy to control with application of a wettable sulfur mixed in a pump up sprayer with a spreader sticker and applied to entire plant including undersides of leaves and deep into the interior of the plant. Sulfur should not be applied if temperature is expected to be above 90°F.

For other common tomato problems, see Tomato cultural tips, pests, and diseases

AND FINALLY

Since it can be hard to find the tomato label as the plant grows, it works well to attach it to the cage at eye level. Use a paper punch to make a hole and attach it to the cage with a twist tie or nursery tape.

Based on an article by Nancy Garrison, March 2006

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