4. When it gets to about 6 inches, carefully take the plant, and pull it, holding on to the bulb. Step 2 on how to harvest fennel: pick carefully. As Florence fennel develops, the stem grows fat and round until it is about the size of a tennis ball. Step 3 on how to harvest fennel… When to Harvest Fennel. Tie … Harvest the bulb once the plant has matured. The leaves of the fennel … Wait any longer, and they can become tough. How to Harvest Fennel Bulbs Use a pair of garden shears or a sharp knife to cut off the plant’s stalks and leaves, leaving an inch or two at the top of the bulb. Harvesting Fennel leaves: You can begin harvesting the leaves of the fennel once you see that the plant is established well. Most varieties of fennel are herbal and will not produce a bulb. Pick off seeds once flowers have withered and gone brown. The Florence fennel, on the other hand, is shorter and has broader foliage in a deeper shade of green. Harvest … 1. Fennel … This takes approximately 65-90 days. You can then remove them carefully. Choose a dry day. HOW TO HARVEST FENNEL POLLEN. Push the heads into a paper bag with the stems poking out. If you’re harvesting fennel bulbs, wait until they are about three inches in diameter. If you’re harvesting seeds, you will want to tie some small bags over the seed heads. This will release seeds into the bags. Snip off the flower heads when the flowers are open and pollen is showing. Make sure that you are not taking more number of leaves at a time as this may cause harm to the plant. 3. These are better suited to be grown indoors. 2. The Florence variety, cultivated for centuries in Italy, is the only bulbing fennel. When slicing you should remove everything, leaving only 9 inches of the fern. Use it for another dinner as a salad addition or side dish. You can harvest the fronds once the plant is established, clip off the top portion to encourage growth. Don’t discard the greenery! The time to reap would be when the bottom part starts to bulb out. Typicaly, fennel … Leave them there for a few days, then shake the heads. Harvesting happens after about 2 months.