Thought to have originated in the region of Northern India thousands of years ago, the lemon tree migrated many miles before making its way to the US with Chris Columbus himself as he crossed the ocean blue. As an evergreen, the lemon is most commonly grown as a commercial crop in Florida and California where warmer temperatures prevail for most of the year. Live in a cooler climate? Never fear. Planting lemon trees in pots that can be moved indoors is a common practice, particularly for dwarf varieties. Make sure to pollinate by hand if growing indoors, unless you frequently invite bees into your living room!
A relatively new kid on the block, the Sungold lemon is a variety of citrus that features bright green- and yellow-striped fruit and variegated, aromatic foliage. It’s a variation of the Eureka lemon, originally discovered in California and later patented. Unique from the Eureka lemon, the Sungold will show green streaks across its rind and leaves. Not to worry: this is natural for the plant and does not indicate a nutrient deficiency as it would in other varieties. If growing Sungolds, make sure to have a thick pair of gloves: this variety of lemon has thorns!
Seed: Not recommended. Lemon trees take 5–15 years to produce fruit when grown from seed. Additionally, because it’s a cultivar, it’s unlikely that any lemon trees you grow from seed will be a true Sungold. But, if your curiosity is peaked, try it out and let us know how it goes!
Seed Depth: 1/2″
Space Between Plants: 12–25′
Space Between Rows: 15–25′
Germination Soil Temperature: 55–75°F
Days for Germination: 14–21
Sow Indoors: Soak seeds overnight in water and plant them 1/2″ deep in moist potting soil. Cover or wrap the pot with a plastic bag and let sit in a warm and sunny spot for a few weeks until the seeds start to grow. Then, remove the plastic and give seedlings at least 4 hours of direct sunlight a day until transplant.
Sow Outdoors: In the citrus belt, trees can be planted at any time. Transplant into containers in the spring.
Vegetative: Plants are usually grown from cuttings which may or may not be grafted onto different root stocks.
Like other citrus fruits, lemons prefer tropical and subtropical climates due to the heat and humidity. Although somewhat hardier than other lemon varieties, Sungolds still prefer temperatures between 77–86°F and tend to cease growing at temperatures below the mid-50s. In the U.S., plants grow best in Zones 9–11.
Natural: Full sun.
Artificial: As plants prefer high heat and levels of sunlight, indoor lemons should be placed near a bright window or grown using HID lamps.
Soil: Prefers loamy or sandy soils but will grow in most soil types as long as they are well-drained. A pH between 5.5 and 6.5 will keep plants healthy and nourished.
Soilless: Plant cuttings in a blend of perlite and well-rotted manure for best growth.
Aquaponics: Will grow in an aquaponic system with a mineral nutrient solution.
Water: Requires medium to high levels of water: a lack of proper irrigation will cause plants to cease fruit production. When trees are young, water two or three times a week. Once established, trees should be irrigated every week to two weeks with three inches of water. Note that although lemon trees require a good deal of water, they will not thrive in soggy soil. Watering should be adjusted based on your zone and rainfall.
Nutrients: Fertilize your lemon tree no more than 4 times per year. Apply the fertilizer equal distance from the root base to the height. For example, if your tree is 10 feet tall, apply fertilizer at a 10 foot radius from the base. Citrus are demanding, which makes sense because of their large, leafy stature and fat, juicy fruit production. Fertilize with compost to provide ample nitrogen. Add phosphorus just before flowering to prevent deficient fruit production.
Foliar: Leaves may be sprayed periodically with a citrus fertilizer in the spring and summer. In specific, use a nitrogen based foliar spray to supplement a large crop.
Pruning: While lemon trees do not require extensive pruning, it should be done each year prior to the trees blooming. Remove any suckers and dead or sickly-looking branches with pruning shears.
Mulching: Mulching is not recommended around the base of the tree but can be ringed approximately 1″ out from the trunk to assist in keeping weeds down and retaining moister. Landscaping fabric may also be used to assist in weed reduction.
Deficiency(s): A lack of iron may cause foliage to turn yellow and green and stunt fruit production.
Companions: Grows well with dill, fennel, yarrow, and other citrus trees.
Harvest: Especially in the first production year, fruits can take anywhere from 6–8 months to ripen. The fruit is ready to harvest when it has turned yellow and firm but not hard as a rock! Fruit can be pulled off or cut with pruning shears to avoid damaging the tree. Take care when harvesting, as lemon trees have sharp spines the can pack a painful prick.
Storage: Can be stored in the refrigerator or cool temperatures for several weeks.
History:This variegated lemon, displaying stripes on both leaves and fruit, makes it a standout in any landscape. This new variety, a ‘sport’ of the Eureka lemon, came about in the 1980s and was developed by a plant pathologist by the name of Martin Harjung who worked for the University of California.
Preserve: Can be preserved through turning into jams, jellies, or marmalades. Perhaps less common but equally delicious are salted lemons. The zest can also be peeled and dehydrated or added to salt to give it a tangy flavor.
Prepare: Versatile and tangy, lemon can be added to juices, cocktails, sauces, desserts, and countless other recipes. Sungolds can juiced, squeezed, or rubbed on a grater to remove the rind as a zest.
Nutritional: Contains significant amount of vitamin C.
Medicinal: Due to its high content of vitamin C, it is considered to have antibacterial and immune-boosting properties. Lemon juice has been associated with weight loss because it aids in digestion and detoxifies the liver. Limonene is an essential oil derived from the rinds of citrus fruits and has been incorporated into pharmaceuticals to relieve heartburn.
Try substituting grocery store lemons with Sungolds in this delicious and vegan Lemon Meringue Pie!