How to grow dill indoors

Dill has a long history of cultivation with roots dating back five centuries to its origins in Russia, the Mediterranean, and Western Africa. In ancient times it was used as a medicinal herb, for currency, and to ward off witches. Over time the strong flavor of dill propelled it into an important culinary resource with its seeds and leaves used in many dishes. These undemanding plants are now commonly grown in indoor herb gardens in containers to provide fresh herbs on demand.

Supplies

Like most other herbs, growing dill indoors is easy, straightforward, and doesn’t require any special equipment. 

Things to keep in mind when potting:

  • Use appropriately sized planting containers.
  • Find a high-quality potting soil that fits your needs.
  • Make sure your chosen seed variety works well for indoor gardening.

Containers - Dill is in the same plant family as carrots and produces a taproot to anchor itself into the soil. In order for it to grow sufficiently, choose containers that are at least 12” deep to accommodate the tap root and a minimum of 6-8” in diameter. If your container does not have sufficient drainage holes in the bottom use a drill (or similar tool) to create some, to allow excess water to drain from the potting soil.

Growing Media - One of the most important components to growing any plants in containers is to start with a high-quality growing substrate. The substrate acts as a reservoir holding the appropriate amount of moisture and nutrients around the roots of the plants; it creates pockets of airspace allowing the roots to breathe; and potting soil anchors the roots, keeping plants supported and upright.

Coconut coir and rich soil are two of the most common options for indoor gardening. Coconut coir has great water retention capabilities, holding approximately 8-10 times its weight in water; it is composed of the brown and white fibers found between the shell and the outer coating of a coconut seed and is popular in hydroponics and indoor gardening. Potting soil is a combination of “soilless” materials made with peat moss or coconut coir, pine bark, perlite, and vermiculite; products are lightweight with good water and nutrient holding capacity.

For more information on growing media check out our full soil guide here.

Seeds - Dill grows best when planted from seed versus trying to transplant seedlings into containers. Seeds are available for purchase in a handful of varieties, each with their own characteristics setting them apart from one another. Bouquet is the most commonly grown type of dill and is used extensively for pickling, although it works well in any recipe calling for either dill leaves or seeds. Fernleaf and Dukat are compact/dwarf varieties, reaching heights of 18” and 3’ respectively; they are both popular for growing dill in containers.

Planting Instructions

Dill does best when planted in containers during cooler temperatures, even when grown indoors. Planting dill in October through early spring typically brings ideal germination and plant growth. 

  1. Fill chosen containers with pre-moistened potting soil, tamping it down slightly to remove any large air pockets. This prevents the potting soil from settling over time.
  2. Scatter seeds across the top of the potting soil and then cover with a small amount of potting soil, or sow them directly into the soil no more than ¼” deep. Maintain a minimum of 4” spacing between the seeds.  
  3. Keep the potting soil slightly damp by misting it with a spray bottle and place in a location where the container won’t be disturbed until the seeds germinate.
  4. After plants germinate and reach a couple of inches tall, thin seedlings to 9-12” apart. Each dill plant produces a substantial amount of leaves and seeds; 1-2 plants per household is sufficient in most cases.

Indoor growing conditions

When growing dill indoors, it’s important to provide plants with the appropriate amount of sunlight and the correct ambient temperature. Optimum growing conditions produce strong, vigorous plants and desirable growth.

The amount of sunlight a plant receives is critical as sunlight drives photosynthesis, the metabolic process turning light energy into chemical energy. Plants take carbon dioxide and using sunlight produce glucose, a source of chemical energy utilized within the plant. Dill prefers full sun conditions when grown outside; indoor plants grow best when placed in a location that receives a minimum of 6 hours of sunlight.

If you don’t have a window that gets 6 hours of sunlight, provide 12 hours of supplemental lighting with incandescent, fluorescent, or LED grow lights. GrowAce explains the different types of grow lights, and how high to position them above plants.

Temperature is also very important when growing dill indoors. Harvest to Table classifies dill as a cool-season herb. Cool-season plants are able to withstand cooler soil and air temperatures; some require cooler temperatures to germinate, grow, set seeds/fruit, and mature.

Dill plants need ambient temperatures above 60℉ to grow, preferring a range between 60 - 75℉. Avoid placing containers too close to windows due to cold air and anywhere else they are exposed to drafts from doors or register vents. The extreme temperature variations cause internal stresses classified as chilling stress (occurring at temperatures below freezing), freezing stress (occurring at low temperatures above freezing), or high-temperature stress (1), all of which hinder plant growth and yields.

How to care for your dill

Dill is an easy to grow plant, providing mature, harvestable plants in a relatively short amount of time. Basic care for plants mimics the management of most other herbs.

  • Water plants until the soil is thoroughly moistened. Then allow the soil to dry out to the depth of 1 - 2” before watering again. An easy way to check soil moisture is to stick your finger down into the potting soil to see how dry it is.
  • Container grown plants require a slightly different fertilizer regime than plants grown outside in the ground. The limited amount of potting soil in a container equates to a limited amount of nutrients available for plant uptake. Container plants quickly deplete these limited nutrients requiring more frequent feeding. Hunker recommends applying fertilizer at half strength every 4-6 weeks when dill is grown indoors. Dill plants don’t need a heavy dose of fertilizer as this affects the flavor or the leaves and seeds.
  • Even if you grow dwarf/compact varieties of dill, plants grown indoors may grow tall and become “leggy” because of insufficient light. Stake plants to provide additional support when they get taller to keep them from slumping or falling over. You can also pinch off the tops of the plants to encourage them to grow outward instead of upward, creating bushier plants.

Harvesting dill leaves and seeds

  • Dill leaves are ready for harvest 6 - 8 weeks after planting seeds as the flower heads are forming. 
  • Seeds are ready to harvest slightly before they ripen and turn tan in color.

Growing dill as a microgreen

Even the best gardeners struggle at times with poor plant growth or plants that won’t thrive. In this case, it’s beneficial to try growing dill indoors as a microgreen.

According to the USDA’s website, microgreens are small, immature plants, harvested after the seed sprouts but before the first true leaves expand. This occurs approximately 7-10 days after seed germination. Compared to mature plants, or even “baby greens”, microgreens pack a wallop of a nutritional punch, with far more nutrition per gram of plant matter than older, mature foliage.

To grow dill microgreens, place 1-2 teaspoons of unsoaked dill seeds on a small tray (4x4 or 5x5” at most) filled with pre-soaked coconut coir. Keep seeds exposed and moist, misting with a spray bottle if any water is needed. Microgreen dill is ready to harvest when it is about 1-2” tall or about 14 days after germination.

Conclusion

An important culinary herb, fresh dill is finding its way into the homes of many, being grown indoors in containers. This cool season crop is easy to grow and requires little more than basic care and maintenance – proper lighting and ambient temperature, adequate water, and a little fertilizer – to produce a plentiful harvest of leaves and seeds; it can even be grown rapidly as a healthy microgreen.

References

  1. Źróbek-Sokolnik, A. (2012) Temperature Stress and Responses of Plants. In P. Ahmad & M. Prasad M. (Eds.), Environmental Adaptations and Stress Tolerance of Plants in the Era of Climate Change. New York, NY: Springer.


Amanda Shiffler

Amanda Shiffler

Most comfortable with soil under her fingernails, Amanda has an enthusiasm for gardening, agriculture, and all things plant related. With an M.S. degree in agriculture and over a decade of experience gardening, she combines her plant knowledge and knack for writing to share what she knows and loves.

Instagram