How and if you fertilize and water a fig tree will depend on several factors including: soil type, soil fertility, weather conditions and location. Fig trees grow satisfactorily in moderately fertile soils without fertilizer. However, fertilizer is needed in soils of low fertility or where competition from other plants is heavy.
Best Growing Conditions...
Sun - The best and most fig fruits will be produced when trees are growing in full sun. However, fig trees that receive a little shade during the hottest part of summer days will still produce good crops.
Soil Type Preferred - Figs will grow reasonably well in most soil types except for very compacted clay or very infertile soils. Fig trees grow and produce the best fruit in well-drained but moist fertile soil that is rich in organic matter. In soil with low fertility it'll be worth your time to mix in some organic compost to the native soil. They like the soil to hold a good supply of water, especially when the fruits are developing in summer, but not so much water that the soil stays constantly soggy or wet.
Soil pH Preferred - Fig trees do best in a slightly acidic soil, somewhere between 6.0 and 6.5 on the pH scale. Whenever growing plants that prefer a specific pH it's a good idea to test the soil. Testing kits are available at most local nursery and garden centers or you can buy soil test kits online here. Your local Extension Service might provide soil testing services as well. Depending on the results of the soil test, you can add lime to raise the pH or soil sulfur to lower the pH (make more acid).
Type Of Fertilizer
Though nitrogen is usually the only needed plant nutrient, other nutrients may be lacking in some areas. If poor growth indicates the need for fertilizer feed your tree. Fig trees can be fed with organic plant foods or inorganic fertilizers, such as 10-10-10. The most essential nutrient figs need is nitrogen. When feeding plants that will put produce on the kitchen table, I always go with organic. Organic plant foods and composts are usually non-burning and will not have chemicals or other inorganic substances in them. The type of fertilizer you choose to use is up to you.
Fertilizing Newly Planted Fig Trees...
When planting a fig during the dormant season, when trees have no leaves, do not apply fertilizer. Wait to fertilize until new growth begins to emerge in spring. Container-grown fig trees can be fertilized at planting time when planted during the spring and summer, however cease fertilization two months prior to the typical first frost date in your area. Late fertilization can stimulate new tender growth that can be damaged from an early freeze.
Feeding Fig Trees Organically
Apply an organic plant food or bloodmeal, cottonseed meal, alfalfa meal or fish emulsion when new growth begins to emerge in spring. Then feed plants again in late spring and mid-summer. Cease feeding fig trees two months prior to the typical first frost date in your area. Alternatively, you can use composted manure or other organic compost materials as a mulch around the tree in late winter or early spring.
Spread the plant food or compost by hand evenly under and around the perimeter of the branches, where the feeder roots will be. The amount of food you apply will depend on the type of plant food. Follow instructions on product label for application rates. As your fig tree grows larger it will require more plant food.
Feeding Fig Trees Inorganically...
Young Trees (1 to 2 Years Old)): Feed young fig trees 1 to 2 years old with a fertilizer that has an analysis of 8-8-8 or 10-10-10. Apply 1 ounce of fertilizer each month starting when new growth begins to emerge in spring through the end of July. The first year, spread the fertilizer evenly over a circle 18" in diameter with the fig plant in the center. Repeat this same fertilization process in March and July of the second year spreading twice as much fertilizer as the year before over a circle 24" in diameter with the fig tree in the center.
Established Trees: Feed established trees with 8-8-8 or 10-10-10 three times a year: late winter, late spring, and mid-summer. Use 1/3 pound of fertilizer per foot of tree height, or follow rates recommended on label. Continue to increase the amount of fertilizer applied yearly until the bushes are 8-10 feet tall.
Spread the fertilizer evenly under and around the perimeter of the branches.
Watering Fig Trees
The frequency and the amount of water a fig tree will need depends to a large extent on the soil and the age of the tree. As a rule of thumb, 1 inch of water per week from rain or irrigation is adequate. Just keep in mind that soil should be moist but not constantly soggy.
Irrigation of young plants is especially important during the first season or two, but be careful not to overwater.
Mature fig trees are quite drought tolerant but will need sufficient water during the fruiting period to produce a good yield of healthy fruit.
Other Tips
- Always keep a sufficient layer of much around your fig trees to control competition from weeds and help retain moisture.
- If the fruit are not reaching maturity and ripening properly, excess fertilizer or drought may be the problem, and fertilization should be reduced. Yellowing and dropping of leaves may indicate drought and the need for supplemental irrigation.
- In lawns, the grass beneath fig plants may wilt in the heat while the rest of the lawn does not. This indicates the figs need water. Figs grown with lawn grasses may require one or more waterings a week during hot, dry periods.
- If figs are frequently cold-damaged in your area, reduce the fertilization recommendations by one-half. If you are attempting to grow figs near the mountains, no fertilizer should be applied to make the plants as cold hardy as possible.