Most herbs grown aeroponically on a tower give a faster and a higher crop yield as well as a superior nutrient content than their counterparts grown in the soil (except rosemary based on our comparative tests.).
From a cooking standpoint, aside from enhanced flavors, aeroponic herbs feature an exceptional texture (i.e.parsley and coriander do not ‘sweat’ when minced.). Furthermore, their vibrant nutrient content allow to keep them fresh for longer periods of time after being harvested (whether refrigerated or not).
In general, aromatic herbs are easy to grow vertically using a Tower Garden. However, some herbs require more attention and maintenance than others in terms of root management and harvesting techniques for optimal results.
Coriander (cilantro):
Rather than putting 3-4 seeds per cube of rockwool, we prefer to plant 5-6 seeds per cube above all when gardening outdoors. In our experience, it allows not only to grow bushier plants but it gives a superior crop for subsequent harvests when cutting the plant partially and aiming at a regrowth strategy.
Cilantro/coriander can be harvested either by pulling it out of the tower fully or by cutting the plant and its roots as short as 5 cm (2 inches) long before being replanted.
The plant can be also harvested in several increments by being cut partially (we recommend to cut ⅓ third of the plant per harvesting session in order to promote an optimal regrowth process).
Although coriander can grow back up to 5 times after having been fully cut, we recommend not to repeat such process more than 3 times and to plant a new seedling after the third harvest.
When cutting/coriander partially or fully but when leaving the plant in the tower aiming at regrowth, in all cases, root management is a must.
Trim/clip the roots on a regular basis. Like with most herbs, the roots of coriander grow fast and produce lots of volume which can easily clog up your tower if not maintained properly.
Use the roots: we invite you to check the various applications of coriander roots in Asian cooking and their health benefits when juiced or eaten raw.
Please note: when the coriander plant starts giving flowers, it loses most of its flavor.
Although cilantro is known to start bolting in temperatures above 80°F (25°C), there are varieties from Southeast Asia (India, Thailand, Vietnam) which can thrive in the heat.
Parsley:
Parsley takes longer than coriander to sprout/grow (mainly referring to curled parsley) but like coriander, it can be harvested up to 5 times as long as the roots are cut/maintained accordingly.
When gardening outdoors, place your tower in a spot which gets partial shade (mainly during the peak of the summer heat).
Make sure that the water inside the nutrient reservoir does not exceed 80°F (25°C) since parsley bolts above such temperature.
Since it takes about 6 weeks for a parsley seed to turn into a seedlings ready to be planted, we do recommend to use each plant for several harvest ensuring a more bountiful crop rotation and availability.
However, around the 3rd/4th harvest, the roots get darker and the new plants produce more stems and less foliage….. Once again, roots need to be maintained/cut regularly.
Mint:
Like coriander or parsley, mint can be harvested repeatedly using the same plan structure. However, when growing mint on a Tower Garden, the root management becomes the main challenge. In fact, mint produces water roots which can crawl in the upper and lower growing sections at the same time.
Avoid planting mint in the lower planting section of the tower as it is almost impossible to avoid a DWC* situation from occurring. We also recommend to avoid planting mint in the the upper planting section since roots can shoot up and clog up the sieve at the top of the tower).
We advise more a maximum of 2–3 harvests per plants due to the challenge of root management as the plant gets older.
Do not over plant: mint grows generously when using a Tower Garden and can easily overwhelm/overshadow the plants in the lower sections.
Thyme:
Thyme takes a long time to sprout and grow on Tower Gardens, but it is totally worth it! It gives incredibly flavorful vibrant plants and can be cut partially/fully for follow-up harvests.
Harvest thyme when it is still young since it loses its flavor and fragrance after it flowers.
Thyme can be planted anywhere on the tower.
For all other aromatic herbs and/or medicinal herbs, we recommend to avoid the top and bottom planting sections when possible and follow the manufacturer’s planting guidelines carefully. However, when growing herbs, in all cases, we insist upon the importance of root management/maintenance above all when the same plant is subject to several harvests.
Aromatic/Medicinal herbs are not only a must for every household/kitchen, but they are also perfect for commercial applications when considering setting up a tower farm.
Dill:
Dill is a plant which needs to be harvested early. Although it turns into a beautiful ornamental plant when overgrown, it can grow big enough to give a trunk-like stem strong enough to damage your tower – as an experiment, we have grown 5 ft (1.5 m) plants which gave enormous volume of roots.
We advise harvesting dill while it is young by pulling the whole plant out of the tower and plant a new seedling (rather than just cutting a few branches at a time).