Fig Tree Masterclass | Growing Fig Trees in a Greenhouse
Summary
In my experience, the most notable advantage of cultivating fig trees in a greenhouse is the ability to kickstart the growing season. Figs are usually ripe between August and the first frost, but for those of us in shorter-season climates that can't provide the 150 to 180 frost-free days needed for figs to ripen reliably, a greenhouse can be a game-changer. It enables the fig trees to rise from dormancy ahead of the last frost date, speeding up their ripening.
The control a greenhouse provides allows me to protect my fig trees from rain, which can drastically affect the fruit quality, particularly during the final ripening stage. Excessive moisture can lead to fruit spoilage, mold, and an increase in fruit flies that could lay larvae into the fruits. As figs absorb water through their skin during the final ripening phase, too much water can decrease the soluble sugar levels in the figs, leading to lower fruit quality and potential spoilage. By raising my figs in a greenhouse, I can maintain a controlled, dry environment that ensures higher fruit quality.
Understanding temperature management in the greenhouse environment is key to successfully growing fig trees. While warmer soil temperatures are necessary for fig trees to wake up from dormancy and start growing, excessive heat can harm their growth. Maintaining an optimal temperature range in the greenhouse is vital.
Ideal soil temperature for fig trees is around 78 degrees Fahrenheit. The soil temperature can be influenced by a combination of external factors, including air temperatures. To determine the soil temperature, I use a soil thermometer. I try to keep the air temperatures in my greenhouse above 50 degrees Fahrenheit whenever possible. If the temperature in the greenhouse exceeds 100-110 degrees Fahrenheit for an extended period, it can damage the growth and fruiting of fig trees and may cause leaf scorch due to increased stress and lack of soil moisture.
It's also crucial to understand that an excess of heat can harm the fig trees in more than one way. Not only can it induce summer dormancy and halt growth, but it can also trigger early fruiting. The fig trees might not have enough growth to support their fruit set while continuing to produce new growth because fruit production requires a lot of energy.
To help my fig tree back into an energy surplus, I remove some of the fruits, even if they're still in their early stages. This allows the tree to redirect its energy towards growth, ensuring it has enough leaves to support the remaining fruits and new leaves.
Water management is another significant aspect of growing fig trees in a greenhouse. Figs require adequate water to support their growth and fruit development. If the water supply is limited, the trees will cease growing. That said, overwatering can lead to root rot and other diseases, so it's crucial to maintain balance. I personally use drip irrigation for consistent and precise watering.
Fertilizing fig trees in a greenhouse is crucial for their growth and development. The best fertilizer should have a good balance of macronutrients and micronutrients. I recommend adding higher quantities of magnesium, calcium, and sulfur, which can be added separately in the form of lime, gypsum, and other soil additives.
Sunlight exposure is another key factor in fig tree growth. The difference in sunlight exposure between greenhouses can affect the number of fruiting branches, leading to more fruit production. Thus, maximizing sunlight exposure through techniques like staking and limb bending can increase bud activation and ultimately fruit production.
Choosing the right container is crucial when growing fig trees in a greenhouse. I prefer using a white plastic pot because it reflects sunlight, helps to keep the soil temperature around 78 degrees Fahrenheit, and prevents the tree from drying out too quickly.
Imagine the delight of biting into a succulent, sweet fig, perfectly ripened, and knowing that you grew it yourself, right at home, in a greenhouse. Whether you're a gardening novice or a seasoned pro, the idea of growing your own fig trees may seem like a daunting task. However, with the right guidance and a little persistence, you too can enjoy the fruits of your labor.
This article will take you on a fascinating journey, unraveling the benefits of growing fig trees in a greenhouse and providing a step-by-step guide on temperature and water management, container selection, pest control, and much more. So, let's embark on this green-thumb adventure, turning your greenhouse into a fig tree paradise.
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Benefits of Growing Fig Trees in a Greenhouse
The most apparent benefit of growing fig trees in a greenhouse is getting an early start to the season. Figs are fall fruits, typically ripening between August and the first frost. For growers in shorter-season climates that lack the 150 to 180 frost-free days needed to reliably ripen main crop figs, using a greenhouse will jumpstart the season.
A controlled greenhouse environment allows your fig trees to awaken from dormancy well before their last frost date, thereby accelerating their ripening dates.
Another significant benefit of using a greenhouse is the ability to shield fig trees from rain, which can critically impact fruit quality, especially in the fig’s final ripening stage. Excessive moisture can lead to spoilage, mold, and an increase in fruit flies that might lay larvae into the fruits.
The skin of the fig is susceptible to absorbing water in the final ripening phase. If the fig absorbs too much water, the soluble sugar (brix) levels drop, leading to a decrease in fruit quality, taste, and potential spoilage. By growing figs in a greenhouse, you can maintain a controlled, dry environment that ensures higher fruit quality.
Growing Figs in a Greenhouse
Heat Management
Heat management is a crucial factor in the successful growth of fig trees in a greenhouse. It’s also one of the few major observable differences when we’re not growing under plastic or glass. Therefore, most of this article will focus on the finer details of heat management. If you can fully understand the topic of temperature and how that relates to growing fig trees in a greenhouse, that will make you the best fig grower possible.
While warmer soil temperatures are essential for fig trees to wake up from dormancy and start growing-- too much heat can be detrimental to their growth. To ensure the optimal growth and fruiting of fig trees, it is necessary to maintain an ideal temperature range in the greenhouse.
Fig Tree Temperature Tolerance
The optimal temperature for fig trees is a soil temperature of 78 degrees Fahrenheit. A combination of external factors all affect the soil temperature including, but not limited to the air temperatures. To determine the soil temperature, I suggest investing in a soil thermometer.
I recommend keeping air temperatures in your greenhouse above 50 degrees Fahrenheit when possible. Cooler air temperatures can lead to a cold soil temperature, which will slow the metabolism of our fig trees and therefore their growth, root development, and nutrient & carbohydrate flow, and more.
If the greenhouse temperature rises above 100-110 degrees Fahrenheit for prolonged periods, it can harm the growth and fruiting of fig trees usually leading to leaf scorch from an increased level of stress and lack of soil moisture.
A consistent soil temperature of 90 to 100 degrees Fahrenheit can cause fig trees to enter a state of summer dormancy which halts their growth. In such cases, fig trees will not continue growing until the soil temperature drops to a suitable level.