Florist Christchurch New Zealand News

Edible Flowers Christchurch Florists

Don't give up on having fresh lettuce just yet

Question: All of my leafy lettuce plants have grown bitter and are going to seed. Can I grow any more or is that it for the season?

Answer: It's a sad fact that the heat we all love in the summer isn't very friendly to our lettuce crop. As soon as the daytime temperatures rise above 24 degrees C and stay there, the average leaf lettuce plant starts thinking about flowering.

Once this process starts, a couple of things happen. The lettuce starts to grow a flower stem to set seeds. It's called "bolting." And even worse, from the culinary point of view, the plant starts to taste quite bitter.

You can delay this process if you can keep the plants cooler. One way is to put up shade over the plants, to cut about 50 per cent of the sun's strength. You can use shade cloth draped over a frame or a section of lattice held up on sticks. This keeps the leaves from heating up and can prolong the harvesting season by a week or two.

But eventually, the plant will succumb to its urge to flower. That is when it should be dug up to make room for other things.

One of the things you can plant is more leaf lettuce.

Sow the seeds of leaf lettuce in the same place. The nice warm weather will help them to germinate quickly. Once you've thinned them out, the young plants will develop quickly under the shade cover. You'll have a crop of late-season leaf lettuce going into the coolest weeks of the season.

Another way to have leafy vegetables through the warmer months of the summer is to grow those that are more resistant to the heat. A couple of varieties spring to mind.

Swiss chard is not bothered at all by the heat, and you can harvest leaves from individual plants all summer and then cut the whole plant early in the fall. Another is New Zealand spinach, which resists bolting and can be cut continually through the season.

Question: I know I'm supposed to cut off any roses once they've finished blooming, but I'm not sure exactly where to make the cut. Can you help?

Answer: Some roses only bloom once, usually in the early summer, while others produce blossoms for a longer period throughout the season. But no matter when they bloom, you'll be helping the rose to maintain its vigour if you remove the flowers as soon as they are finished.

Where to make the cut depends on the number of leaflets on each leaf stem. Look at the first leaf stem below the faded flower. It will usually have five leaflets. Now, look further down the stem and you'll see that this suddenly changes to a stem with seven leaflets. Your cut should be just above the first joint where there are seven leaflets.

You can cut even lower down the stem. The best way to prune a rose is to cut just above a joint where the new shoot will grow outwards from the centre of the plant, so that new branches don't grow inwards.

Just to add a slight wrinkle, there are some floribunda, grandiflora and hybrid tea roses that grow three leaflets near the flower, and five leaflets lower down. In this case, cut just above the first leaf stem with five leaflets.

Question: There are medium sized trees on our street that grow large bunches of tiny cream flowers in late spring and early summer. They smell like lilac. What are they?

Answer: They are Japanese lilacs. They can be grown anywhere with full sun or half-shade conditions.