Growing garlic in a greenhouse allows you to enjoy fresh, homegrown garlic year-round. The controlled environment of a greenhouse enables you to customize conditions to optimize garlic growth. But exactly how long does it take to go from planting cloves to harvesting bulbs? Let’s explore the garlic growth stages and timeline in a greenhouse.
Overview of Garlic Growth Cycle
To grow garlic, you plant single cloves, which then sprout and grow into full bulbs. The growth stages are .
- Planting – Inserting garlic cloves into soil
- Sprouting – Shoots emerge from cloves in 1-2 weeks
- Leaf growth – Greens continue growing for 4-6 weeks
- Bulb formation – Bulbs swell underground starting at 2 months
- Maturing – Lower leaves yellow as bulbs mature after 6-9 months
- Harvesting – Garlic can be harvested when 50% of leaves are brown
It usually takes between 6 and 9 months from planting to harvest, but this depends on the type of bulb, the weather, and the size of bulb that is wanted. Let’s look at a more detailed timeline.
Timeline of Garlic Growth in a Greenhouse
Here is what you can expect in terms of duration for each growth phase when growing garlic in a greenhouse:
Planting
This first stage is fast – just a day or two to get the cloves inserted into soil or containers
Sprouting
- Expect to see sprouts emerging in 1-2 weeks after planting.
- Hardneck varieties may sprout slightly sooner than softneck.
Leaf Growth
- Leafy greens will continue growing taller for 4-6 weeks after sprouting.
- Provide adequate sunlight and nutrients during this stage.
Bulb Formation
- Swelling of bulbs underground begins around 2 months after planting.
- Bulb growth stage lasts a minimum of 4-5 months.
- Larger bulbs may take 6-8 months to fully size up.
Maturing
- Lower leaves start browning and dying back around 6-8 months after planting.
- The garlic is mature when about 50% of the leaves have turned brown.
Harvesting
- Ready for harvest once maturity indicators are seen.
- Typical duration is 6-9 months from planting date.
- Earliest harvest may be possible just over 6 months.
Factors Influencing Timeline
Several factors can accelerate or delay garlic’s maturation timeline in a greenhouse:
- Variety – Hardneck garlic may mature faster than softneck.
- Planting Method – Pre-sprouted bulbs mature faster than cloves.
- Conditions – Warmer temps and adequate water slightly speed growth.
- Soil Fertility – Rich soil with nutrients encourages faster maturity.
- Bulb Size – Bigger bulbs need longer underground growth time.
Growing Year-Round Garlic
One great thing about a greenhouse is that you can space out your plantings so you can harvest garlic all year long.
- Start new cloves every 2-3 months for a continuous supply.
- Maintain ideal temperatures and moisture levels for each stage.
- Harvest mature bulbs as needed while new plantings continue developing.
However, ensure bulbs have adequate time to size up before harvesting – around 6-9 months depending on variety and conditions. Rushing growth can result in undersized bulbs.
Monitoring Progress for Harvest
Pay close attention to leaves and test bulbs to determine optimal harvest timing:
- Monitor soil temperature and moisture weekly.
- Inspect leaves for yellowing/browning.
- Gently dig up a test bulb to check size about 6 months after planting.
- Best timing is when 50% of leaves are brown and bulbs reach desired size.
If grown in the right way, garlic takes about 6 to 9 months to grow from a clove to a fully grown bulb that is ready to be picked. Staggered plantings allow for year-round harvests. Keep an eye on the soil, the leaves, and the bulbs to find out when they are fully grown and ready to be picked for plump, tasty homegrown garlic.
TL;DR
- Total greenhouse growth: 6-9 months
- Sprouting: 1-2 weeks after planting
- Leaf growth: 4-6 weeks after sprouting
- Bulb swelling: Starts at 2 months
- Maturing: 6-8 months when lower leaves brown
- Harvest: When 50% of leaves are brown
- Stagger plantings for year-round harvests
- Check soil, leaves, test bulbs to time harvest
Garlic varieties for greenhouses
Before you start growing garlic in your greenhouse, it’s good to know about the main types of garlic. We are focusing on true varieties of garlic garlic, so we exclude elephant garlic.
Hardneck garlic gets its name from the stiff, woody central stalk, or “neck,” that runs through the middle of the bulb and extends above the ground. This “neck” is also where the garlic scapes, or flower stalks, emerge during the growing season.
- Larger bulbs with fewer big cloves: Hardneck garlic bulbs usually have fewer cloves than softneck bulbs. But these kinds of garlic tend to have cloves that are bigger and more evenly spaced. Usually, they are arranged in a single layer around the main stalk.
- Hardneck garlic does best in colder climates, which makes it perfect for greenhouses that aren’t heated.
- Scapes: Hardneck garlic produces curly flower stalks (scapes). People often cut them off to get the plant to focus more on growing bulbs. They are, however, edible, so you can use them in food.
- Because their skin is thinner, these types of garlic usually don’t last as long when stored as softneck varieties.
- Flavor: A lot of people think that hardneck garlic tastes stronger and more complex than softneck garlic.
Rocambole: Known for its thin skin and easy peeling. A popular variety is ‘Spanish Roja’.
Purple Striped: Varieties like ‘Starbright’ and ‘Chesnok’ are good for roasting.
Porcelain: Features a plump bulb with only a few fat cloves making the largest bulbs with the largest cloves. Good for storing, with varieties like ‘Georgian Crystal’ and ‘Romanian Red’.
Softneck garlic is another primary type of garlic that is commonly sold in grocery stores. Softneck garlic lacks a stiff, woody central stalk, making the neck soft and flexible. This characteristic also makes softneck garlic easier to braid for storage.
- Claves: Garlic bulbs with soft necks usually have more cloves than bulbs with hard necks. Each clove is usually smaller, and they can be arranged in more than one layer inside the bulb.
- Climate adaptability: Softneck varieties do better in warmer climates and can grow in a wider range of conditions.
- If you grow softneck garlic, it doesn’t usually make flower stalks. Instead, all of its energy goes into making a bigger bulb.
- Storage: One of the best things about softneck types is that they last longer when stored. There are several layers of papery skin on the cloves, which helps the garlic stay fresh for a long time.
- Taste: Softneck garlic usually has a milder taste than hardneck garlic, but this can change.
Artichoke: This is the most commonly grown commercial garlic. It has a couple of concentric rows of cloves and is difficult to peel. A well-known variety is ‘Red Toch’.
Silverskins: This type has silvery, white skins and is composed of many small cloves. They also have a sturdy neck that is easily braided. The flavor is usually stronger than Artichokes. Varieties include ‘Nootka Rose’ and ‘Rose du Var’.
4 simple steps to grow garlic from cloves:
- From a fresh bulb, separate the garlic cloves. Be careful not to break the cloves where they join at the base, in the middle. If the base is destroyed, it will not develop. You also want to use a healthy bulb. Make sure each clove keeps its papery husk.
- Each garlic clove should be pushed 3 to 4 inches into the ground, or 2 inches if you’re using mulch. The pointed end should face up, and the root side should face down. Space the cloves about 4 to 6 inches apart, and if you plant them in rows, space them 18 inches apart.
- Plant garlic cloves and cover them with mulch. Use an organic mulch like straw. The plants get food from this, and the soil stays cool and moist.
- Spread garlic cloves on the side of the plant or use compost to fertilize it. Feed it several times before the bulbs start to swell or if you see leaves turning yellow.
Watch This Before You Plant Garlic
FAQ
How long does it take to grow garlic in a greenhouse?
It takes between 6 to 8 months until the garlic is at the “ready to pick” stage.
What is the best month to plant garlic?
The best time to plant garlic is September to mid-November or after the first frost. You’ll probably have some room in your garden boxes around then. You harvested a lot, and there’s not all that much left to sow. Enter garlic: the easiest vegetable there is.
What should you not plant next to garlic?
Here are some more plants that should not be planted with garlic:Asparagus (Asparagus officinalis)Chives (Allium schoenoprasum)Beans (Phaseolus and Vicia)Leeks (Allium porrum)Onions (Allium cepa)Ornamental onions (Allium spec. )Parsley (Petroselinum crispum)Peas (Pisum sativum).
How do I know when my garlic is ready to harvest?
Garlic is ready to harvest when about half of the lower leaves have turned yellow or brown and started to die back. The plant may also begin to bend or fall over. If you planted hardneck garlic, the flower stalk (scape) will have straightened up when the garlic is ready.