When to Plant Caper Seeds
Plant in late Spring after the last killing frost has passed.
Where to Plant Caper Seeds
Caper plants require dry and hot arid climates and long days of strong sunlight to thrive. Capers are hardy in USDA Growing Zones 9 - 11 and can withstand high heat temperatures over the Summer months. In these zones, they can act as an evergreen. Due to their temperate nature, they cannot survive over Winter in Zones 8 and below outside. Cooler zones are recommended to plant in a pot and brought inside during the Winter.
How to Plant Caper Seeds
Seeds require cold moist stratification to germinate. Soak seeds in a jar for 24 hours in warm water (no need to keep the water warm once it cools to room temperature). Wrap seeds in a damp towel and seal in a plastic bag or jar and refrigerate for 65 - 70 Days. Remove from the refrigerator and soak seeds again in warm water for another 24 hours. Plant seeds 1/4 inch deep in a mixture of potting soil, perlite, and sand (50/25/25) - Use 4-6" pots and install 4-5 seeds per pot. Make sure soil stays moist & keep in a warm (70°F-85°F) place in part or full sun. *Note: Caper Seeds are notoriously challenging to germinate from seed and can take up to 3 - 4 weeks to germinate, and typically in low percentages.
When seedlings reach 3 - 5 inches in height, transplant to a 1-Gallon container filled with the same planting mix and ratio used for the seeds. Make sure not to disturb their root systems. Water and cover each container with a plastic bag & place the container in a shady spot. After 1 week, cut the top of the bag to allow the plant to acclimate to its environment. Increase the size of the opening after another 10 days. After another week, remove the plastic bag and place the plants in a shaded area. If transplanting to the ground, plant in early Spring after the danger of frost has passed. If planting in a larger container, transplant when your plant reaches 6 - 8 inches tall.
How to Harvest Capers
There are 6 stages at which Capers can be harvested. It's best to pick them by hand in the morning when they’ve reached the desired size. It is said that the smaller they are, the more desirable (and expensive) they are. Capers are ready to pick when they are a dark olive green color, and at least a 1/4 inch wide with a tightly closed flower bud. You can also harvest them as they get larger in size, about a 1/2 inch, and when they start expanding into their flower form.